Radio Control Electrics Bob Kopski CHARGE months column going address most-often-askedabout topics charging particular gonna see make charging system will handle popular motor battery packs system present ed very simple reliable inex pensive can built nearly anybody requires no soldering special tools instruments material can purchased Radio Shack hobby shop hardware auto parts stores Its based something probably already have Astro Leisure similar charger addition well use to see some past lessons Basic Electricity can applied real work ing Electric hardware Lets get charger system pictured consists four main items conventional charger Electric cars planes Voltage Inverter Radio Shack catalog no 22-129 simple resistor bank resistors also Radio Shack some assort ed small items such lamp cord clips ordinary household switch wall box assorted wood pieces some nutz boltz purpose system permit easy charging motor battery pack youre likely find up 14 cells system no longer necessary split up two six-cell seven-cell packs otherwise connected series model make 12-cell 14-cell packs get completely frustrated trying charge ordinary single seven-cell packs grieve no longer answer simple circuit device shown figure unit powered via fairly heavy input cables car battery must connected directly battery posts input 12 volts powers Voltage Inverter turn doubles 12 volts 24 volts capable delivering up three amps output current elevated voltage level very efficient reliable manner have run couple Inverters hours overstressed condition no problems no overheating standard three-way household light switch really single-pole doublethrow switch selects either incoming 12 volt positive line 24 volt positive Voltage Inverter output allocates selection via homemade resistor net works cut voltage steps regular charger Just choose voltage job hand will discussed later resistor bank pictured really pair two distinct resistor sets resistors chosen readily avail able types capable handling just slightly over three amps Thus rated consistent Voltage verter ratings schematic shows resistor bank consists six oneohm 10-watt resistors connected series string series resistors forms 'coarse' currentadjustment device powered switch output arm simpler resistor bank special grouping few resistors powered negative auto battery power input lead serves fine adjustment device resistors mechanically elec trically assembled simple posts consist ing ordinary No 6 No 8 No 10 machine screw hardware normal use resistors will get hot ab solutely necessary assemble resistor banks manner like shown photo will melt solder solder assembled please save yourself trouble way An aluminum foil reflector double-sticky-taped %-in birch plywood resistor plate prevents burning wooden mount 50 Model Aviation Bobs highly-versatile heavy-duty charging system its easily made read column readily-available partseverything mounts 9 13-in 1/4-ln ply base Pro tective cage aluminum window screen material Note cage rails wooden located over resistorsbut over resistor leads Thats because resistors get HOT during charge tube merely holds various chaer cords Photo below gives better idea lead lengthsinput leads doubled lengths No 16 lamp cord wire color-coded light positive dark negative must connected proper terminals car battery Ni-Cd flight pack being recharged drawl ng gives circuit design 1 L SPECIAL NOTE VOLTAGE INVERTER RUNS CONSTANTLY DRAWS VERY LITTLE WHEN 24V POSITION IS NOT IN USE INVERTER IN-LINE FUSE HOLDER RADIO SHACK VOLTAGE BLACK#22129 RED 24V GREEN oJ 12V 3-WAY HOUSEHOLD WALL SWITCH TOP VIEW WIRE N UT 12 0R4-24V SWITCH SELCTED SIXtlA lOW RESISTORS RADIO SHACK #271-131 OHMS 0 2 3 4 5 6 0 1/4 RED 0 OLK 0~~~1 vW 3/4 TOP VIEW RESISTOR ASSEMBLY DOTTED WIRING BOTTOM SIDE FOUR O47n SW LARGE AUTORESISTORS ERY CLIPSRADIO SHACK *271130 TO MOTOR BATTERYCHARGER simple cover screen made ordi nary household aluminum door screen epoxied wooden rails prevents acciden tal contact hot resistors two resistor banks have multiple-output taps various individual resistor intersections screw posts become input connections charger clip leads connected red positive charger clip lead connect ed seven coarse positive resistor screw posts black negative charger clip lead goes remaining four fine negative screw 'posts' conventional charger output con nector plugs model battery pack other aspects its operation remain normal except some small points made later Thus charg er timer switch used before charger current meter used before fact familiar meter strument youll need know thing working OK Now some words about works past two columns Basic Electricity installments know current circuit determined available voltage divided cir cuit resistance also know voltage charging sourcethe auto batteryis ordinarily 12 volts fact can does vary somewhat over somewhat under 12 volts 24 volt Inverter output will follow input variation Also know model power-system battery being Ni-Cd dis plays fairly predictable terminal voltage too has some variation around nominal point basic importance understand what meant available circuit voltage schematic consistent familiar practice obvious model battery can charged source voltage greater two Thus familiar example six-cell NiContinued page 148 Twin resistor bank 1 mounts 5 x 7 piece hIn birch piy Note aluminum foil heatrefiector Four resistors ieft 047 ohm posts 27k-in centers Larger resistors ohm mounted 3-in centers DO NOT SOLDER THE LEADS TO THE POSTSthe joints might meit servicel Wiring backside resistor bank iooks ilke Center Use No 16 No 18 Wirestranded soi id soiid easier handie Note wiring smaii resistors bottom wires simple series Detali shot R resistor bank shows use brightpiated 632 machine screws nuts washers lock washers Screws 1 1A long spaced /z span aiiow resistor bodies bunch upthey must remain separated proper cooling May1985 51 WIRE NUT 5-6 16 GAUGE LAMP CORD PAIRS inside switch boxwire nuts used connect everything Switch screws near side connected red output iead Voltage inverter L other R goes positive resistor set hidden back switch ties car batterys posi tive input cabie black fused lead Voltage Inverter Note strain relief cable clamp discussed quite few club newsletters subject noise mufflers Most about necessity improve noise situation using better mufflers Almost club Ive involved last 15 years least formal muffler rule Some quite specific Nowadays almost everyone uses mufflers engines However middle Sixties almost nobody used Engines loud muffler propo nents claimed use mufflers would guarantee against loss fly ing field due noise problems early mufflers did lot quiet engines expense losing lot power Modern mufflers good job reduc ing noise sacrificing power remember thinking time club Western Ohio Radio Kontrol Socie ty required use mufflers about 1967 question time before everyone would forget what like before started using mufflers noise complaints would start again As know situation upon us As much hate think unless dra matic new improvements made mufflers two-cycle engines lot flying fields will lost other alternative can see clubs noise problems ban two-cycle engines favor four-cycle engines thats done wonder long will take flying field neighbors forget before four-cycle engines required start complaining again second item Id like share club newsletters pub lished Mount Rainier Radio Con trol Society Newsletter Tacoma WA Its semi-anonymous author Bill D wrote Old Threat Finally Identified Field Psychologist Glitchus Crashemup commonly known glitch has finally identified after years research dread malady preys upon certain segment species Homo Sapiens known RC Pilots normally lurking open fields grown men play model air craft glitch very dangerous full plumage adult male should approached experienced glitch hunters wielding loaded field strength meters has bite produces im mediate reactions beginning ner vous shaking twitching thumbs sequence symptoms often followed cries dont have Splintering thudding noises occur almost immediately point vic tim usually lapses depression may become militant approached next few minutes glitch invisible real imagined experience enemy should reported immediate ly field psychologist Ron Van Putte 111 Sleepy Oaks Rd Ft Walton Beach FL 32548 RC Electrics/Kopski Continued page 51 Cd will under charge eventually reach voltage its terminals equal about 15 x 6 about nine volts since Ni-Cds float up 15 volts per cell under charge take source volt age auto battery 12 volts avail able circuit voltage simply three volts difference 12 nine volts voltage appears across charging circuit resistance ear lier lessons circuit current charg ing current established choosing suitable resistor charge system design has plenty resistors choose Lets figure out make choice Last month saw several ways write Ohms Law Youll remember law relates three common elec trical terms voltage V current resistance R particular saw resistance can found dividing available circuit voltage ACV cir cuit current like R As example lets say six-cell pack made up 800 MAh cells Three amps very good charge current use 148 Model Aviation -I A monthly publication covering International RC Soaring Scene $1 6/yr US Canada & Mexico $24/yr elsewhere via airmail Post Office Box 269 Peterborough NH 03458 convenient Thus R lts divided 3 amps 1 ohm Clearly have connect charger clip leads resistor posts total resistance tapped off ohm could simply put black lead negative 0 ohms post red lead positive 1 ohm tap thats just sure everything OK simply note charger ammeter reading dial up timer switch should now clear what have really same old charger used using now choice supply voltages very convenient set selectable resistors fact no need go through arithmetic shown above practice just select desired source voltage switch connect charger input leads two resistor sets point highest resistance lowest current connect model battery start timer switch check ammeter reading Move clip leads lower values resistance increase charge current value desired over three amps An effective procedure arriving needed resistance start both high resistance taps move through coarse set steps ohm until youre close tobut low sideof desired current move through fine steps fine tune desired value can motor bat tery up 14 cells further note practical nature charging current will gradually decrease during time required charge because terminal voltage model pack will slowly rise available circuit voltage voltage across chosen resistor will decrease could just keep changing taps its necessary After two uses will become clear much current drop will can simply start little above desired value because know cur rent will slowly drop below its average current thats important provid ed variation too great similar vein car battery will gradually lower its voltage during busy day flying taps used earlier day will ones chosen later beauty design should always able ad just good charge Now lets examine special frustrating case seven-cell system read ers have told trouble exper ience getting good charge such motor pack Following six-cell example above can see sevencell pack will climb total voltage Signal Guard blocks random noise oft-frequency signals can cause loss control air land RC models Signal Guard responds sig nals its own precisely tuned fre quency ignoring static noise craft itself Plus additional amplification allows control operators visual limit Special Introductory Offer 87w about 15 x 7 105 voltsor moreas charge progresses 12 volt auto battery available circuit voltage 12 15 volts Obviously small voltage requires very small circuit resistance attain reasonable charg ing current Its under conditions things like good battery-clip contact good charger connection model power system extremely importantand also often unreliable beginning charge battery voltage relatively low say about 12 x 7 84 volts available circuit voltage 12 6 volts Thus beginning charge later ACV varies over 21and would charge want spend time flying less time money repairing crashed model Signal Guard answer Call toll-free 1-800-468-8215 order Signal Guard TM major credit card send $150 check money order Thlls PO Box 30179 Portland OR 97230 Oregon call collect 503-257-0912 current given circuit resistance Thus typical seven-cell pack 12 volt supply can have both unreliable circuit resistance highly variable ACV together can result very questionable charge course charge system shown least allows easy adjustment current-controlling taps theres better approach problem system presented can very good job charging seven-cell packs switching 24 volt position tap ping off enough resistance establish desired current two example bat tery voltages mentioned above ACV would 24 135 24 156 volts respectively May1985 149 90 day warranty. Selected dealerships available variation case clearly very small thus charge current will much constant Also selected resis tance will over four ohmsmuch would used above much stable forgiving contact resis tance variation Thus excellent charge available seven-cell packs should clear discussions above can generalized number cells fact smaller number cells model battery controlled charge con versely smaller ACV un reliable charge As rule thumb suggest using 12 volt position six fewer cells 24 volt option seven cells Naturally charging 14 cells will worst case regard possible use 24 volts time can fact almost left out 12/24 switch just used 24 volt Voltage Inverter output However considera tion highlights two known disadvantages charge system may relatively inefficient depending its used charging techniques use~ power auto battery needed charge model battery wasted power appearsyou guessed itas heat waste larger greater ACV Therefore some may consider prudent use lower two available source voltages possi ble Also lower-voltage position necessary have very small packs such small-capacity two three fourcell configurations As side point interest power wasted heat other charg er really no big deal should annoyance Consider common household 60 watt light bulb Surely no would wrap hand around thats few minutesits hot purpose light bulb provide light heat Only very small amount con sumed electrical power ever makes its way form light energyits virtual ly wasted heat Thus com mon light bulb very inefficient device second disadvantage charge system previously-mentioned threeamp limit Remember limit imposed Voltage Inverter specifica tion choice resistors Lets apply some Basic Electricity illus trate latter point resistors used Radio Shack 10 watt components description much power can safely dissi pate heat Last month learned power resistor such flashlight lamp discussed equal x x R case know resis tance Lets pick ohm resistor know power ratingits 10 watts two pieces information can find maximum current allowed thus P R Pxl0 atts rewriting 12 = 10 1 i/i3l6 amps example can see use fulness having some knowledge basic electricity back disadvantage itself As mentioned earlier three amps very convenient current charging 800 mali cells what use Thats because charger timer switches 15-minute clocks 3 amps x 15 minutes 45 ampminutes 4500% mAh just little short label capacity cells question represents safe charge put nearly-dead pack what about 12 Ah cells Well takes three amps about 12/3 x 60 24 minutes reach label capacity would charge about 20 minutes perfectly safe carefree charge dead Thus disadvantage have charge 12 Ah packs 15 minutes dial five timer other hand much better getting questionable charge some other less-controlled way have down path will SAILPLANES WORLD iSOlA Coffee Rd Modesto CA 95355 Sailplanes International Krause MultiPlex Wanitschek Wik & Roke Sport-Scale-F3B European Hardware Accessories Send $500 Cat & Price List 209 577-0506 IntducIng. Ereb cr11 RIC Idle-Bar Glow Plugs Long Short Also.Only $169 Traditional line non-idle bar Glow Plugs Six Types 3 Heat Ranges High Performance Glow Element Blow Proof Seal Only I Swanson Associates_ PO Box 151 e NJ 07470 5/Mi ______ 150 Model Aviation ELECTRIC MODEL & SAILPLANE SPECIALISTS 1981 World Soaring Champ DWIGHT HOLLEY IS PROUD TO ANNOUNCE NEW COMPANY TO HELP BOTH BEGINNER & EXPERT FLY INTO THE NEW ERA OF ELECTRIC AIRCRAFT WE ALSO OFFER SELECT FEW PURE SAILPLANES FREE DEMONSTRATION FLIGHTS CHECK OUT UNGlUE TEST FLIGHTS OF YOUR NEW PLANES CALL OR WRITE FOR FREE DESCRIPTIVE FLYER UPS C 00 FOR IMMEDIATE SHIPMENT ELECTRIC KITS IN STOCK AEROBATIC OLOTIMER SPORT SCALE GLIDERS HOLLEYS SILENT FLIGHT 203 748-0083 151 CHESTNUT RIDGE ROAD BETHEL CT 06801 FEATURING ONLY STATE OF THE ART ITEMS 01 51 01 01 n 0 z -I 0 r r 01 01 5 a z vi r m 5 know what mean Now lets talk about what chargers YOU can use system As far know Astros Leisures products capable handling 24 volt input such two 12 volt batteries series will work think Leisure digital chargera very popular productmay used above some limited voltage should check Roland Boucher before try applies whether youre using approach other higher source voltage Also Astros 4005D very popular charger because its built-in adjust ability However please note charger capable handling high input voltage charge just few cells defectits simply intended dissipate several watts its versatile solid state adjust ment circuitry suggest set con trol full click switch rotary control use system will work just fine Also chargers such pictured article 4005D have trickle charge circuit allows small current flow model battery after high-rate charge terminated time switch Astro uses small lamp Leisure small resistor across internal timer contacts components may able tolerate 24 volt input real ly needed purposes anyway Per sonally would simply disconnect such internal parts usually just wired timer screw terminals theres matter some charg ers having large fixed internal resistors particular charging job Leisure charger pictured herein way has switch-selectable resistor use popular RC cars having six seven-cell 12 aH packs resistors simply become resistance complete circuit charging system ordi narily should pose no problem application cannot tolerate add ed resistance simply short resistors out wire jumper Finally charger shown held system baseboard doublesticky-backed Velcro Radio Shack As such easily lifted assembly use usual input output wires have left intact rfo internal modifications have made its perfectly normal device removed environment charge system simple system quite work able very wide range applications theres can done fact Ill presenting deluxe charge system later will based two modified Voltage Inverters supplemented highly-efficient smoothly-adjustable solid state switching mode electronic current-regulator will charge batteries up 30 volts beyond four amps SAILPLANE LAUNCH EQUIPMENT FOR EVERY FIELD $23495 source QUIET FLIGHT Supplies hi-starts electric motors& reducers bat te r aes pa rachu tes tow line drums accessories braided nylon Iinethe PRO PHEY PROPHET 941CURTISS ROBINaL CRATE kits VISA MASTERCARD h EDAVEY EUSYSTEMS m VU CORPORATION ONE WOOD LANEMALVERNPA 19355 215644-6772 Write call information May1985 151 iro Box 10630 Lorain Ohio 44055 APhone 216282-8354 Peanut Scale Models Piper Vigabond Piper Cub 0linsgn 125 utdeor kits nh. $650 Light Indoor kits.. $695 Sport Scale Models 22 Span PC-6 Porter Taylor Craft Stinsan Voyager Rubber CO2 Power PC-B POft&Kits each. $750 Soort Models An Embryo Model 18 Span designed wiol beginners Experts HARD-TO-FIND ITEMS FOR YOUR BUILDING NEEDS Early Bird Tissue br Antique Aircratt S595 True Olde Japanese Tissue 10 3 colors 95 Japanese Tissue 12 6 colors $395 Microlite Plain$325 Silver$395 Microfilm Glue Solvent Condenser Paper 3 sheets 5375 Plan Service over 17 Scale Sport Scale & Peanut Scale Rubber Strip 020 thro 085each 5175 3/32 tliru 5/32each 5195 Winder 61 395 Mark 1161 195 Complete Line 01 Brown CO2 Motors Balsa Wood Outdoor & Indoor Sheets & Strips Add 10% Poutage mum Postage $150 COMPLETE CATALOG 5150 C battery yet Secinied POWRZOOM$36995 RETRBEVER$26495 El S 4 hi 01 01 z 01 a a 201 SE 12thStreeo Pompano Beach FL 33060 305-785-7978 INC TIlE LANOIIIG GEAf eEoPtE Tired kil landing goaro 181 dont III ynar biggie properly o & II Eagineering can salvo yaor problems * CesIum boilt yoor eteds & specs guaranteed III * Strong & durable wiIbslad Ike laugheet aiding * It & Engineering gear will wark & keep yoor biggie flying * Ia clock roplacoineat gear popular models Byron PIlls Christ Eagle CAP 21 gals0 ISA J-3 CUB Air Tack Pawnee Eagle Nosen Big Slick Cbamp Citabria g & g madels Snapper Stinger Seapper Tue 4 THE COMPETITIONS VIEW 'I OF THE WINDSONG I. C, 0 0 N 0 DODGSON DESIGNS 2904 SW CAMANO DRIVE CAMANO ISLAND WA 9825i2J What makes Windsong best plane have deadair lightlift gusting 25 MPH winds thermal contest What makes windsong best plane have x-country race Some say 11to 1 aspect ratio clean solidcore wing no spoiler bays disturb airflow Others say Eppler 214 airfoil combined exclusive full-span camber changing capability including elevator compensated 80 degree flaps reflexible ailerons fact design innovations contribute Windsongs total design concept its unprecedented performance WITH THE WINOSONG THE WHOLE IS TRULY GREATER THAN THE SUM OF ITS PARTS Windsong 19995Camano 15995Pixy 14995 Send 2 stamps catalog VHS video tape too can made readily-avail able materials youll have build some sophisticated electronics make work Please forward questions SASE author Happy Electric Landings Bob Kopski 25 West End Dr Lansdale PA 19446 RC Giant Scale/Beckman Continued page 53 dont miss information con tact Lee Taylor 216 Willow Ave Rose ville CA 95678 phone number 916 783-4190 next have information all-time favorite events STARS Scale Rally Olean NY scheduled July 6 7 year another event limited Giant Scale dont see much else flying site hospitality fantastic place might see Giant Scale aircraft IMAA Fun-Fly Festival IMAA bash year set July 18-21 Mobile AL fifth year event note time change August July Like Nats FFF rotating around different loca tions year like idea since gives IMAA members around country chance participate what Im hearing will another great Im putting weight just reading menus picnic ban quet Yes Mortimer Giant Scalers other things besides fly big birds things eat info available Don Godfrey 91 Blackstone Ave Binghamton NY 13903 telephone 607 724-0115 Bob Beckman 8248 Holly Grove Ct Manassas VA 22110 RC Pylon Racing/Hager Continued page 54 does make wheel pants last longer Well doesnt shock actually destroys wheel pants eliminated attaching land ing gear General Electrics clear bath tub caulking compound assure get proper shock mount slide wheel pant up landing gear place caulking compound backside landing gear pant gear meet Slide back down line up hole gear pant clean unwant ed caulk away Caution Clean out screw hole could lock up wheels install Now assuming final attach ment ie wheel pants painted use Loc-Tite product secure wheels tighten down Allen wrench four-way wrench Place piece vinyl tape over hole unit complete experience using method has nothing convenience factor No special wrench tighten nut easy replacement easy paint touch-up lower-portion damage easy in-field repair replacement longer life wheel pants Hopefully experience will same See next mouth Bill Hager 706 Glen Haven Dr Conroe TX 77385 RC Helicopters/Jolly Continued page 55 really impressed some particular Airtronics 94554 heavyduty servo has proved excellent choice use Helicopter servo features coreless motor ball-bearingsupported output shaft good centering great strength Ive found servo particular value using flybarless rotor system Because heavy feed back loads some servos fail short time have putting lot hours set 94554s prototype GMP flybarless system over last nine months am very satisfied After reading above might think 94554 good flybarless machine quite contrary little thing works well under strenuous en vironment theyre better Bell Hiller system Another product found very useful American RCs new Lok N-Start starting system really dont like starting belts have admit starting cones work fine until starter slips off cone either goes through cabin adds burnished look finish Scale ship So what Lok-N-Start Basically unit consists two parts adapter shaft telescopes over starting shaft machine held place setscrews starter-adap ter another shaft screws onto end starter has Torrington clutch other end Starting accom plished inserting starter over adapter squeezing switch Because Torrington one-way clutch starter cannot keep engine ac celerating once have gotten fire Best off no friction necessary except transferred Torrington very clean simple system should have thought years ago works great months photos addition photo Jack Schultzs coaxial scratchbuilt have scratch-built-fuselage 152 ModelAviation
Edition: Model Aviation - 1985/05
Page Numbers: 50, 51, 148, 149, 150, 151, 152
Radio Control Electrics Bob Kopski CHARGE months column going address most-often-askedabout topics charging particular gonna see make charging system will handle popular motor battery packs system present ed very simple reliable inex pensive can built nearly anybody requires no soldering special tools instruments material can purchased Radio Shack hobby shop hardware auto parts stores Its based something probably already have Astro Leisure similar charger addition well use to see some past lessons Basic Electricity can applied real work ing Electric hardware Lets get charger system pictured consists four main items conventional charger Electric cars planes Voltage Inverter Radio Shack catalog no 22-129 simple resistor bank resistors also Radio Shack some assort ed small items such lamp cord clips ordinary household switch wall box assorted wood pieces some nutz boltz purpose system permit easy charging motor battery pack youre likely find up 14 cells system no longer necessary split up two six-cell seven-cell packs otherwise connected series model make 12-cell 14-cell packs get completely frustrated trying charge ordinary single seven-cell packs grieve no longer answer simple circuit device shown figure unit powered via fairly heavy input cables car battery must connected directly battery posts input 12 volts powers Voltage Inverter turn doubles 12 volts 24 volts capable delivering up three amps output current elevated voltage level very efficient reliable manner have run couple Inverters hours overstressed condition no problems no overheating standard three-way household light switch really single-pole doublethrow switch selects either incoming 12 volt positive line 24 volt positive Voltage Inverter output allocates selection via homemade resistor net works cut voltage steps regular charger Just choose voltage job hand will discussed later resistor bank pictured really pair two distinct resistor sets resistors chosen readily avail able types capable handling just slightly over three amps Thus rated consistent Voltage verter ratings schematic shows resistor bank consists six oneohm 10-watt resistors connected series string series resistors forms 'coarse' currentadjustment device powered switch output arm simpler resistor bank special grouping few resistors powered negative auto battery power input lead serves fine adjustment device resistors mechanically elec trically assembled simple posts consist ing ordinary No 6 No 8 No 10 machine screw hardware normal use resistors will get hot ab solutely necessary assemble resistor banks manner like shown photo will melt solder solder assembled please save yourself trouble way An aluminum foil reflector double-sticky-taped %-in birch plywood resistor plate prevents burning wooden mount 50 Model Aviation Bobs highly-versatile heavy-duty charging system its easily made read column readily-available partseverything mounts 9 13-in 1/4-ln ply base Pro tective cage aluminum window screen material Note cage rails wooden located over resistorsbut over resistor leads Thats because resistors get HOT during charge tube merely holds various chaer cords Photo below gives better idea lead lengthsinput leads doubled lengths No 16 lamp cord wire color-coded light positive dark negative must connected proper terminals car battery Ni-Cd flight pack being recharged drawl ng gives circuit design 1 L SPECIAL NOTE VOLTAGE INVERTER RUNS CONSTANTLY DRAWS VERY LITTLE WHEN 24V POSITION IS NOT IN USE INVERTER IN-LINE FUSE HOLDER RADIO SHACK VOLTAGE BLACK#22129 RED 24V GREEN oJ 12V 3-WAY HOUSEHOLD WALL SWITCH TOP VIEW WIRE N UT 12 0R4-24V SWITCH SELCTED SIXtlA lOW RESISTORS RADIO SHACK #271-131 OHMS 0 2 3 4 5 6 0 1/4 RED 0 OLK 0~~~1 vW 3/4 TOP VIEW RESISTOR ASSEMBLY DOTTED WIRING BOTTOM SIDE FOUR O47n SW LARGE AUTORESISTORS ERY CLIPSRADIO SHACK *271130 TO MOTOR BATTERYCHARGER simple cover screen made ordi nary household aluminum door screen epoxied wooden rails prevents acciden tal contact hot resistors two resistor banks have multiple-output taps various individual resistor intersections screw posts become input connections charger clip leads connected red positive charger clip lead connect ed seven coarse positive resistor screw posts black negative charger clip lead goes remaining four fine negative screw 'posts' conventional charger output con nector plugs model battery pack other aspects its operation remain normal except some small points made later Thus charg er timer switch used before charger current meter used before fact familiar meter strument youll need know thing working OK Now some words about works past two columns Basic Electricity installments know current circuit determined available voltage divided cir cuit resistance also know voltage charging sourcethe auto batteryis ordinarily 12 volts fact can does vary somewhat over somewhat under 12 volts 24 volt Inverter output will follow input variation Also know model power-system battery being Ni-Cd dis plays fairly predictable terminal voltage too has some variation around nominal point basic importance understand what meant available circuit voltage schematic consistent familiar practice obvious model battery can charged source voltage greater two Thus familiar example six-cell NiContinued page 148 Twin resistor bank 1 mounts 5 x 7 piece hIn birch piy Note aluminum foil heatrefiector Four resistors ieft 047 ohm posts 27k-in centers Larger resistors ohm mounted 3-in centers DO NOT SOLDER THE LEADS TO THE POSTSthe joints might meit servicel Wiring backside resistor bank iooks ilke Center Use No 16 No 18 Wirestranded soi id soiid easier handie Note wiring smaii resistors bottom wires simple series Detali shot R resistor bank shows use brightpiated 632 machine screws nuts washers lock washers Screws 1 1A long spaced /z span aiiow resistor bodies bunch upthey must remain separated proper cooling May1985 51 WIRE NUT 5-6 16 GAUGE LAMP CORD PAIRS inside switch boxwire nuts used connect everything Switch screws near side connected red output iead Voltage inverter L other R goes positive resistor set hidden back switch ties car batterys posi tive input cabie black fused lead Voltage Inverter Note strain relief cable clamp discussed quite few club newsletters subject noise mufflers Most about necessity improve noise situation using better mufflers Almost club Ive involved last 15 years least formal muffler rule Some quite specific Nowadays almost everyone uses mufflers engines However middle Sixties almost nobody used Engines loud muffler propo nents claimed use mufflers would guarantee against loss fly ing field due noise problems early mufflers did lot quiet engines expense losing lot power Modern mufflers good job reduc ing noise sacrificing power remember thinking time club Western Ohio Radio Kontrol Socie ty required use mufflers about 1967 question time before everyone would forget what like before started using mufflers noise complaints would start again As know situation upon us As much hate think unless dra matic new improvements made mufflers two-cycle engines lot flying fields will lost other alternative can see clubs noise problems ban two-cycle engines favor four-cycle engines thats done wonder long will take flying field neighbors forget before four-cycle engines required start complaining again second item Id like share club newsletters pub lished Mount Rainier Radio Con trol Society Newsletter Tacoma WA Its semi-anonymous author Bill D wrote Old Threat Finally Identified Field Psychologist Glitchus Crashemup commonly known glitch has finally identified after years research dread malady preys upon certain segment species Homo Sapiens known RC Pilots normally lurking open fields grown men play model air craft glitch very dangerous full plumage adult male should approached experienced glitch hunters wielding loaded field strength meters has bite produces im mediate reactions beginning ner vous shaking twitching thumbs sequence symptoms often followed cries dont have Splintering thudding noises occur almost immediately point vic tim usually lapses depression may become militant approached next few minutes glitch invisible real imagined experience enemy should reported immediate ly field psychologist Ron Van Putte 111 Sleepy Oaks Rd Ft Walton Beach FL 32548 RC Electrics/Kopski Continued page 51 Cd will under charge eventually reach voltage its terminals equal about 15 x 6 about nine volts since Ni-Cds float up 15 volts per cell under charge take source volt age auto battery 12 volts avail able circuit voltage simply three volts difference 12 nine volts voltage appears across charging circuit resistance ear lier lessons circuit current charg ing current established choosing suitable resistor charge system design has plenty resistors choose Lets figure out make choice Last month saw several ways write Ohms Law Youll remember law relates three common elec trical terms voltage V current resistance R particular saw resistance can found dividing available circuit voltage ACV cir cuit current like R As example lets say six-cell pack made up 800 MAh cells Three amps very good charge current use 148 Model Aviation -I A monthly publication covering International RC Soaring Scene $1 6/yr US Canada & Mexico $24/yr elsewhere via airmail Post Office Box 269 Peterborough NH 03458 convenient Thus R lts divided 3 amps 1 ohm Clearly have connect charger clip leads resistor posts total resistance tapped off ohm could simply put black lead negative 0 ohms post red lead positive 1 ohm tap thats just sure everything OK simply note charger ammeter reading dial up timer switch should now clear what have really same old charger used using now choice supply voltages very convenient set selectable resistors fact no need go through arithmetic shown above practice just select desired source voltage switch connect charger input leads two resistor sets point highest resistance lowest current connect model battery start timer switch check ammeter reading Move clip leads lower values resistance increase charge current value desired over three amps An effective procedure arriving needed resistance start both high resistance taps move through coarse set steps ohm until youre close tobut low sideof desired current move through fine steps fine tune desired value can motor bat tery up 14 cells further note practical nature charging current will gradually decrease during time required charge because terminal voltage model pack will slowly rise available circuit voltage voltage across chosen resistor will decrease could just keep changing taps its necessary After two uses will become clear much current drop will can simply start little above desired value because know cur rent will slowly drop below its average current thats important provid ed variation too great similar vein car battery will gradually lower its voltage during busy day flying taps used earlier day will ones chosen later beauty design should always able ad just good charge Now lets examine special frustrating case seven-cell system read ers have told trouble exper ience getting good charge such motor pack Following six-cell example above can see sevencell pack will climb total voltage Signal Guard blocks random noise oft-frequency signals can cause loss control air land RC models Signal Guard responds sig nals its own precisely tuned fre quency ignoring static noise craft itself Plus additional amplification allows control operators visual limit Special Introductory Offer 87w about 15 x 7 105 voltsor moreas charge progresses 12 volt auto battery available circuit voltage 12 15 volts Obviously small voltage requires very small circuit resistance attain reasonable charg ing current Its under conditions things like good battery-clip contact good charger connection model power system extremely importantand also often unreliable beginning charge battery voltage relatively low say about 12 x 7 84 volts available circuit voltage 12 6 volts Thus beginning charge later ACV varies over 21and would charge want spend time flying less time money repairing crashed model Signal Guard answer Call toll-free 1-800-468-8215 order Signal Guard TM major credit card send $150 check money order Thlls PO Box 30179 Portland OR 97230 Oregon call collect 503-257-0912 current given circuit resistance Thus typical seven-cell pack 12 volt supply can have both unreliable circuit resistance highly variable ACV together can result very questionable charge course charge system shown least allows easy adjustment current-controlling taps theres better approach problem system presented can very good job charging seven-cell packs switching 24 volt position tap ping off enough resistance establish desired current two example bat tery voltages mentioned above ACV would 24 135 24 156 volts respectively May1985 149 90 day warranty. Selected dealerships available variation case clearly very small thus charge current will much constant Also selected resis tance will over four ohmsmuch would used above much stable forgiving contact resis tance variation Thus excellent charge available seven-cell packs should clear discussions above can generalized number cells fact smaller number cells model battery controlled charge con versely smaller ACV un reliable charge As rule thumb suggest using 12 volt position six fewer cells 24 volt option seven cells Naturally charging 14 cells will worst case regard possible use 24 volts time can fact almost left out 12/24 switch just used 24 volt Voltage Inverter output However considera tion highlights two known disadvantages charge system may relatively inefficient depending its used charging techniques use~ power auto battery needed charge model battery wasted power appearsyou guessed itas heat waste larger greater ACV Therefore some may consider prudent use lower two available source voltages possi ble Also lower-voltage position necessary have very small packs such small-capacity two three fourcell configurations As side point interest power wasted heat other charg er really no big deal should annoyance Consider common household 60 watt light bulb Surely no would wrap hand around thats few minutesits hot purpose light bulb provide light heat Only very small amount con sumed electrical power ever makes its way form light energyits virtual ly wasted heat Thus com mon light bulb very inefficient device second disadvantage charge system previously-mentioned threeamp limit Remember limit imposed Voltage Inverter specifica tion choice resistors Lets apply some Basic Electricity illus trate latter point resistors used Radio Shack 10 watt components description much power can safely dissi pate heat Last month learned power resistor such flashlight lamp discussed equal x x R case know resis tance Lets pick ohm resistor know power ratingits 10 watts two pieces information can find maximum current allowed thus P R Pxl0 atts rewriting 12 = 10 1 i/i3l6 amps example can see use fulness having some knowledge basic electricity back disadvantage itself As mentioned earlier three amps very convenient current charging 800 mali cells what use Thats because charger timer switches 15-minute clocks 3 amps x 15 minutes 45 ampminutes 4500% mAh just little short label capacity cells question represents safe charge put nearly-dead pack what about 12 Ah cells Well takes three amps about 12/3 x 60 24 minutes reach label capacity would charge about 20 minutes perfectly safe carefree charge dead Thus disadvantage have charge 12 Ah packs 15 minutes dial five timer other hand much better getting questionable charge some other less-controlled way have down path will SAILPLANES WORLD iSOlA Coffee Rd Modesto CA 95355 Sailplanes International Krause MultiPlex Wanitschek Wik & Roke Sport-Scale-F3B European Hardware Accessories Send $500 Cat & Price List 209 577-0506 IntducIng. Ereb cr11 RIC Idle-Bar Glow Plugs Long Short Also.Only $169 Traditional line non-idle bar Glow Plugs Six Types 3 Heat Ranges High Performance Glow Element Blow Proof Seal Only I Swanson Associates_ PO Box 151 e NJ 07470 5/Mi ______ 150 Model Aviation ELECTRIC MODEL & SAILPLANE SPECIALISTS 1981 World Soaring Champ DWIGHT HOLLEY IS PROUD TO ANNOUNCE NEW COMPANY TO HELP BOTH BEGINNER & EXPERT FLY INTO THE NEW ERA OF ELECTRIC AIRCRAFT WE ALSO OFFER SELECT FEW PURE SAILPLANES FREE DEMONSTRATION FLIGHTS CHECK OUT UNGlUE TEST FLIGHTS OF YOUR NEW PLANES CALL OR WRITE FOR FREE DESCRIPTIVE FLYER UPS C 00 FOR IMMEDIATE SHIPMENT ELECTRIC KITS IN STOCK AEROBATIC OLOTIMER SPORT SCALE GLIDERS HOLLEYS SILENT FLIGHT 203 748-0083 151 CHESTNUT RIDGE ROAD BETHEL CT 06801 FEATURING ONLY STATE OF THE ART ITEMS 01 51 01 01 n 0 z -I 0 r r 01 01 5 a z vi r m 5 know what mean Now lets talk about what chargers YOU can use system As far know Astros Leisures products capable handling 24 volt input such two 12 volt batteries series will work think Leisure digital chargera very popular productmay used above some limited voltage should check Roland Boucher before try applies whether youre using approach other higher source voltage Also Astros 4005D very popular charger because its built-in adjust ability However please note charger capable handling high input voltage charge just few cells defectits simply intended dissipate several watts its versatile solid state adjust ment circuitry suggest set con trol full click switch rotary control use system will work just fine Also chargers such pictured article 4005D have trickle charge circuit allows small current flow model battery after high-rate charge terminated time switch Astro uses small lamp Leisure small resistor across internal timer contacts components may able tolerate 24 volt input real ly needed purposes anyway Per sonally would simply disconnect such internal parts usually just wired timer screw terminals theres matter some charg ers having large fixed internal resistors particular charging job Leisure charger pictured herein way has switch-selectable resistor use popular RC cars having six seven-cell 12 aH packs resistors simply become resistance complete circuit charging system ordi narily should pose no problem application cannot tolerate add ed resistance simply short resistors out wire jumper Finally charger shown held system baseboard doublesticky-backed Velcro Radio Shack As such easily lifted assembly use usual input output wires have left intact rfo internal modifications have made its perfectly normal device removed environment charge system simple system quite work able very wide range applications theres can done fact Ill presenting deluxe charge system later will based two modified Voltage Inverters supplemented highly-efficient smoothly-adjustable solid state switching mode electronic current-regulator will charge batteries up 30 volts beyond four amps SAILPLANE LAUNCH EQUIPMENT FOR EVERY FIELD $23495 source QUIET FLIGHT Supplies hi-starts electric motors& reducers bat te r aes pa rachu tes tow line drums accessories braided nylon Iinethe PRO PHEY PROPHET 941CURTISS ROBINaL CRATE kits VISA MASTERCARD h EDAVEY EUSYSTEMS m VU CORPORATION ONE WOOD LANEMALVERNPA 19355 215644-6772 Write call information May1985 151 iro Box 10630 Lorain Ohio 44055 APhone 216282-8354 Peanut Scale Models Piper Vigabond Piper Cub 0linsgn 125 utdeor kits nh. $650 Light Indoor kits.. $695 Sport Scale Models 22 Span PC-6 Porter Taylor Craft Stinsan Voyager Rubber CO2 Power PC-B POft&Kits each. $750 Soort Models An Embryo Model 18 Span designed wiol beginners Experts HARD-TO-FIND ITEMS FOR YOUR BUILDING NEEDS Early Bird Tissue br Antique Aircratt S595 True Olde Japanese Tissue 10 3 colors 95 Japanese Tissue 12 6 colors $395 Microlite Plain$325 Silver$395 Microfilm Glue Solvent Condenser Paper 3 sheets 5375 Plan Service over 17 Scale Sport Scale & Peanut Scale Rubber Strip 020 thro 085each 5175 3/32 tliru 5/32each 5195 Winder 61 395 Mark 1161 195 Complete Line 01 Brown CO2 Motors Balsa Wood Outdoor & Indoor Sheets & Strips Add 10% Poutage mum Postage $150 COMPLETE CATALOG 5150 C battery yet Secinied POWRZOOM$36995 RETRBEVER$26495 El S 4 hi 01 01 z 01 a a 201 SE 12thStreeo Pompano Beach FL 33060 305-785-7978 INC TIlE LANOIIIG GEAf eEoPtE Tired kil landing goaro 181 dont III ynar biggie properly o & II Eagineering can salvo yaor problems * CesIum boilt yoor eteds & specs guaranteed III * Strong & durable wiIbslad Ike laugheet aiding * It & Engineering gear will wark & keep yoor biggie flying * Ia clock roplacoineat gear popular models Byron PIlls Christ Eagle CAP 21 gals0 ISA J-3 CUB Air Tack Pawnee Eagle Nosen Big Slick Cbamp Citabria g & g madels Snapper Stinger Seapper Tue 4 THE COMPETITIONS VIEW 'I OF THE WINDSONG I. C, 0 0 N 0 DODGSON DESIGNS 2904 SW CAMANO DRIVE CAMANO ISLAND WA 9825i2J What makes Windsong best plane have deadair lightlift gusting 25 MPH winds thermal contest What makes windsong best plane have x-country race Some say 11to 1 aspect ratio clean solidcore wing no spoiler bays disturb airflow Others say Eppler 214 airfoil combined exclusive full-span camber changing capability including elevator compensated 80 degree flaps reflexible ailerons fact design innovations contribute Windsongs total design concept its unprecedented performance WITH THE WINOSONG THE WHOLE IS TRULY GREATER THAN THE SUM OF ITS PARTS Windsong 19995Camano 15995Pixy 14995 Send 2 stamps catalog VHS video tape too can made readily-avail able materials youll have build some sophisticated electronics make work Please forward questions SASE author Happy Electric Landings Bob Kopski 25 West End Dr Lansdale PA 19446 RC Giant Scale/Beckman Continued page 53 dont miss information con tact Lee Taylor 216 Willow Ave Rose ville CA 95678 phone number 916 783-4190 next have information all-time favorite events STARS Scale Rally Olean NY scheduled July 6 7 year another event limited Giant Scale dont see much else flying site hospitality fantastic place might see Giant Scale aircraft IMAA Fun-Fly Festival IMAA bash year set July 18-21 Mobile AL fifth year event note time change August July Like Nats FFF rotating around different loca tions year like idea since gives IMAA members around country chance participate what Im hearing will another great Im putting weight just reading menus picnic ban quet Yes Mortimer Giant Scalers other things besides fly big birds things eat info available Don Godfrey 91 Blackstone Ave Binghamton NY 13903 telephone 607 724-0115 Bob Beckman 8248 Holly Grove Ct Manassas VA 22110 RC Pylon Racing/Hager Continued page 54 does make wheel pants last longer Well doesnt shock actually destroys wheel pants eliminated attaching land ing gear General Electrics clear bath tub caulking compound assure get proper shock mount slide wheel pant up landing gear place caulking compound backside landing gear pant gear meet Slide back down line up hole gear pant clean unwant ed caulk away Caution Clean out screw hole could lock up wheels install Now assuming final attach ment ie wheel pants painted use Loc-Tite product secure wheels tighten down Allen wrench four-way wrench Place piece vinyl tape over hole unit complete experience using method has nothing convenience factor No special wrench tighten nut easy replacement easy paint touch-up lower-portion damage easy in-field repair replacement longer life wheel pants Hopefully experience will same See next mouth Bill Hager 706 Glen Haven Dr Conroe TX 77385 RC Helicopters/Jolly Continued page 55 really impressed some particular Airtronics 94554 heavyduty servo has proved excellent choice use Helicopter servo features coreless motor ball-bearingsupported output shaft good centering great strength Ive found servo particular value using flybarless rotor system Because heavy feed back loads some servos fail short time have putting lot hours set 94554s prototype GMP flybarless system over last nine months am very satisfied After reading above might think 94554 good flybarless machine quite contrary little thing works well under strenuous en vironment theyre better Bell Hiller system Another product found very useful American RCs new Lok N-Start starting system really dont like starting belts have admit starting cones work fine until starter slips off cone either goes through cabin adds burnished look finish Scale ship So what Lok-N-Start Basically unit consists two parts adapter shaft telescopes over starting shaft machine held place setscrews starter-adap ter another shaft screws onto end starter has Torrington clutch other end Starting accom plished inserting starter over adapter squeezing switch Because Torrington one-way clutch starter cannot keep engine ac celerating once have gotten fire Best off no friction necessary except transferred Torrington very clean simple system should have thought years ago works great months photos addition photo Jack Schultzs coaxial scratchbuilt have scratch-built-fuselage 152 ModelAviation
Edition: Model Aviation - 1985/05
Page Numbers: 50, 51, 148, 149, 150, 151, 152
Radio Control Electrics Bob Kopski CHARGE months column going address most-often-askedabout topics charging particular gonna see make charging system will handle popular motor battery packs system present ed very simple reliable inex pensive can built nearly anybody requires no soldering special tools instruments material can purchased Radio Shack hobby shop hardware auto parts stores Its based something probably already have Astro Leisure similar charger addition well use to see some past lessons Basic Electricity can applied real work ing Electric hardware Lets get charger system pictured consists four main items conventional charger Electric cars planes Voltage Inverter Radio Shack catalog no 22-129 simple resistor bank resistors also Radio Shack some assort ed small items such lamp cord clips ordinary household switch wall box assorted wood pieces some nutz boltz purpose system permit easy charging motor battery pack youre likely find up 14 cells system no longer necessary split up two six-cell seven-cell packs otherwise connected series model make 12-cell 14-cell packs get completely frustrated trying charge ordinary single seven-cell packs grieve no longer answer simple circuit device shown figure unit powered via fairly heavy input cables car battery must connected directly battery posts input 12 volts powers Voltage Inverter turn doubles 12 volts 24 volts capable delivering up three amps output current elevated voltage level very efficient reliable manner have run couple Inverters hours overstressed condition no problems no overheating standard three-way household light switch really single-pole doublethrow switch selects either incoming 12 volt positive line 24 volt positive Voltage Inverter output allocates selection via homemade resistor net works cut voltage steps regular charger Just choose voltage job hand will discussed later resistor bank pictured really pair two distinct resistor sets resistors chosen readily avail able types capable handling just slightly over three amps Thus rated consistent Voltage verter ratings schematic shows resistor bank consists six oneohm 10-watt resistors connected series string series resistors forms 'coarse' currentadjustment device powered switch output arm simpler resistor bank special grouping few resistors powered negative auto battery power input lead serves fine adjustment device resistors mechanically elec trically assembled simple posts consist ing ordinary No 6 No 8 No 10 machine screw hardware normal use resistors will get hot ab solutely necessary assemble resistor banks manner like shown photo will melt solder solder assembled please save yourself trouble way An aluminum foil reflector double-sticky-taped %-in birch plywood resistor plate prevents burning wooden mount 50 Model Aviation Bobs highly-versatile heavy-duty charging system its easily made read column readily-available partseverything mounts 9 13-in 1/4-ln ply base Pro tective cage aluminum window screen material Note cage rails wooden located over resistorsbut over resistor leads Thats because resistors get HOT during charge tube merely holds various chaer cords Photo below gives better idea lead lengthsinput leads doubled lengths No 16 lamp cord wire color-coded light positive dark negative must connected proper terminals car battery Ni-Cd flight pack being recharged drawl ng gives circuit design 1 L SPECIAL NOTE VOLTAGE INVERTER RUNS CONSTANTLY DRAWS VERY LITTLE WHEN 24V POSITION IS NOT IN USE INVERTER IN-LINE FUSE HOLDER RADIO SHACK VOLTAGE BLACK#22129 RED 24V GREEN oJ 12V 3-WAY HOUSEHOLD WALL SWITCH TOP VIEW WIRE N UT 12 0R4-24V SWITCH SELCTED SIXtlA lOW RESISTORS RADIO SHACK #271-131 OHMS 0 2 3 4 5 6 0 1/4 RED 0 OLK 0~~~1 vW 3/4 TOP VIEW RESISTOR ASSEMBLY DOTTED WIRING BOTTOM SIDE FOUR O47n SW LARGE AUTORESISTORS ERY CLIPSRADIO SHACK *271130 TO MOTOR BATTERYCHARGER simple cover screen made ordi nary household aluminum door screen epoxied wooden rails prevents acciden tal contact hot resistors two resistor banks have multiple-output taps various individual resistor intersections screw posts become input connections charger clip leads connected red positive charger clip lead connect ed seven coarse positive resistor screw posts black negative charger clip lead goes remaining four fine negative screw 'posts' conventional charger output con nector plugs model battery pack other aspects its operation remain normal except some small points made later Thus charg er timer switch used before charger current meter used before fact familiar meter strument youll need know thing working OK Now some words about works past two columns Basic Electricity installments know current circuit determined available voltage divided cir cuit resistance also know voltage charging sourcethe auto batteryis ordinarily 12 volts fact can does vary somewhat over somewhat under 12 volts 24 volt Inverter output will follow input variation Also know model power-system battery being Ni-Cd dis plays fairly predictable terminal voltage too has some variation around nominal point basic importance understand what meant available circuit voltage schematic consistent familiar practice obvious model battery can charged source voltage greater two Thus familiar example six-cell NiContinued page 148 Twin resistor bank 1 mounts 5 x 7 piece hIn birch piy Note aluminum foil heatrefiector Four resistors ieft 047 ohm posts 27k-in centers Larger resistors ohm mounted 3-in centers DO NOT SOLDER THE LEADS TO THE POSTSthe joints might meit servicel Wiring backside resistor bank iooks ilke Center Use No 16 No 18 Wirestranded soi id soiid easier handie Note wiring smaii resistors bottom wires simple series Detali shot R resistor bank shows use brightpiated 632 machine screws nuts washers lock washers Screws 1 1A long spaced /z span aiiow resistor bodies bunch upthey must remain separated proper cooling May1985 51 WIRE NUT 5-6 16 GAUGE LAMP CORD PAIRS inside switch boxwire nuts used connect everything Switch screws near side connected red output iead Voltage inverter L other R goes positive resistor set hidden back switch ties car batterys posi tive input cabie black fused lead Voltage Inverter Note strain relief cable clamp discussed quite few club newsletters subject noise mufflers Most about necessity improve noise situation using better mufflers Almost club Ive involved last 15 years least formal muffler rule Some quite specific Nowadays almost everyone uses mufflers engines However middle Sixties almost nobody used Engines loud muffler propo nents claimed use mufflers would guarantee against loss fly ing field due noise problems early mufflers did lot quiet engines expense losing lot power Modern mufflers good job reduc ing noise sacrificing power remember thinking time club Western Ohio Radio Kontrol Socie ty required use mufflers about 1967 question time before everyone would forget what like before started using mufflers noise complaints would start again As know situation upon us As much hate think unless dra matic new improvements made mufflers two-cycle engines lot flying fields will lost other alternative can see clubs noise problems ban two-cycle engines favor four-cycle engines thats done wonder long will take flying field neighbors forget before four-cycle engines required start complaining again second item Id like share club newsletters pub lished Mount Rainier Radio Con trol Society Newsletter Tacoma WA Its semi-anonymous author Bill D wrote Old Threat Finally Identified Field Psychologist Glitchus Crashemup commonly known glitch has finally identified after years research dread malady preys upon certain segment species Homo Sapiens known RC Pilots normally lurking open fields grown men play model air craft glitch very dangerous full plumage adult male should approached experienced glitch hunters wielding loaded field strength meters has bite produces im mediate reactions beginning ner vous shaking twitching thumbs sequence symptoms often followed cries dont have Splintering thudding noises occur almost immediately point vic tim usually lapses depression may become militant approached next few minutes glitch invisible real imagined experience enemy should reported immediate ly field psychologist Ron Van Putte 111 Sleepy Oaks Rd Ft Walton Beach FL 32548 RC Electrics/Kopski Continued page 51 Cd will under charge eventually reach voltage its terminals equal about 15 x 6 about nine volts since Ni-Cds float up 15 volts per cell under charge take source volt age auto battery 12 volts avail able circuit voltage simply three volts difference 12 nine volts voltage appears across charging circuit resistance ear lier lessons circuit current charg ing current established choosing suitable resistor charge system design has plenty resistors choose Lets figure out make choice Last month saw several ways write Ohms Law Youll remember law relates three common elec trical terms voltage V current resistance R particular saw resistance can found dividing available circuit voltage ACV cir cuit current like R As example lets say six-cell pack made up 800 MAh cells Three amps very good charge current use 148 Model Aviation -I A monthly publication covering International RC Soaring Scene $1 6/yr US Canada & Mexico $24/yr elsewhere via airmail Post Office Box 269 Peterborough NH 03458 convenient Thus R lts divided 3 amps 1 ohm Clearly have connect charger clip leads resistor posts total resistance tapped off ohm could simply put black lead negative 0 ohms post red lead positive 1 ohm tap thats just sure everything OK simply note charger ammeter reading dial up timer switch should now clear what have really same old charger used using now choice supply voltages very convenient set selectable resistors fact no need go through arithmetic shown above practice just select desired source voltage switch connect charger input leads two resistor sets point highest resistance lowest current connect model battery start timer switch check ammeter reading Move clip leads lower values resistance increase charge current value desired over three amps An effective procedure arriving needed resistance start both high resistance taps move through coarse set steps ohm until youre close tobut low sideof desired current move through fine steps fine tune desired value can motor bat tery up 14 cells further note practical nature charging current will gradually decrease during time required charge because terminal voltage model pack will slowly rise available circuit voltage voltage across chosen resistor will decrease could just keep changing taps its necessary After two uses will become clear much current drop will can simply start little above desired value because know cur rent will slowly drop below its average current thats important provid ed variation too great similar vein car battery will gradually lower its voltage during busy day flying taps used earlier day will ones chosen later beauty design should always able ad just good charge Now lets examine special frustrating case seven-cell system read ers have told trouble exper ience getting good charge such motor pack Following six-cell example above can see sevencell pack will climb total voltage Signal Guard blocks random noise oft-frequency signals can cause loss control air land RC models Signal Guard responds sig nals its own precisely tuned fre quency ignoring static noise craft itself Plus additional amplification allows control operators visual limit Special Introductory Offer 87w about 15 x 7 105 voltsor moreas charge progresses 12 volt auto battery available circuit voltage 12 15 volts Obviously small voltage requires very small circuit resistance attain reasonable charg ing current Its under conditions things like good battery-clip contact good charger connection model power system extremely importantand also often unreliable beginning charge battery voltage relatively low say about 12 x 7 84 volts available circuit voltage 12 6 volts Thus beginning charge later ACV varies over 21and would charge want spend time flying less time money repairing crashed model Signal Guard answer Call toll-free 1-800-468-8215 order Signal Guard TM major credit card send $150 check money order Thlls PO Box 30179 Portland OR 97230 Oregon call collect 503-257-0912 current given circuit resistance Thus typical seven-cell pack 12 volt supply can have both unreliable circuit resistance highly variable ACV together can result very questionable charge course charge system shown least allows easy adjustment current-controlling taps theres better approach problem system presented can very good job charging seven-cell packs switching 24 volt position tap ping off enough resistance establish desired current two example bat tery voltages mentioned above ACV would 24 135 24 156 volts respectively May1985 149 90 day warranty. Selected dealerships available variation case clearly very small thus charge current will much constant Also selected resis tance will over four ohmsmuch would used above much stable forgiving contact resis tance variation Thus excellent charge available seven-cell packs should clear discussions above can generalized number cells fact smaller number cells model battery controlled charge con versely smaller ACV un reliable charge As rule thumb suggest using 12 volt position six fewer cells 24 volt option seven cells Naturally charging 14 cells will worst case regard possible use 24 volts time can fact almost left out 12/24 switch just used 24 volt Voltage Inverter output However considera tion highlights two known disadvantages charge system may relatively inefficient depending its used charging techniques use~ power auto battery needed charge model battery wasted power appearsyou guessed itas heat waste larger greater ACV Therefore some may consider prudent use lower two available source voltages possi ble Also lower-voltage position necessary have very small packs such small-capacity two three fourcell configurations As side point interest power wasted heat other charg er really no big deal should annoyance Consider common household 60 watt light bulb Surely no would wrap hand around thats few minutesits hot purpose light bulb provide light heat Only very small amount con sumed electrical power ever makes its way form light energyits virtual ly wasted heat Thus com mon light bulb very inefficient device second disadvantage charge system previously-mentioned threeamp limit Remember limit imposed Voltage Inverter specifica tion choice resistors Lets apply some Basic Electricity illus trate latter point resistors used Radio Shack 10 watt components description much power can safely dissi pate heat Last month learned power resistor such flashlight lamp discussed equal x x R case know resis tance Lets pick ohm resistor know power ratingits 10 watts two pieces information can find maximum current allowed thus P R Pxl0 atts rewriting 12 = 10 1 i/i3l6 amps example can see use fulness having some knowledge basic electricity back disadvantage itself As mentioned earlier three amps very convenient current charging 800 mali cells what use Thats because charger timer switches 15-minute clocks 3 amps x 15 minutes 45 ampminutes 4500% mAh just little short label capacity cells question represents safe charge put nearly-dead pack what about 12 Ah cells Well takes three amps about 12/3 x 60 24 minutes reach label capacity would charge about 20 minutes perfectly safe carefree charge dead Thus disadvantage have charge 12 Ah packs 15 minutes dial five timer other hand much better getting questionable charge some other less-controlled way have down path will SAILPLANES WORLD iSOlA Coffee Rd Modesto CA 95355 Sailplanes International Krause MultiPlex Wanitschek Wik & Roke Sport-Scale-F3B European Hardware Accessories Send $500 Cat & Price List 209 577-0506 IntducIng. Ereb cr11 RIC Idle-Bar Glow Plugs Long Short Also.Only $169 Traditional line non-idle bar Glow Plugs Six Types 3 Heat Ranges High Performance Glow Element Blow Proof Seal Only I Swanson Associates_ PO Box 151 e NJ 07470 5/Mi ______ 150 Model Aviation ELECTRIC MODEL & SAILPLANE SPECIALISTS 1981 World Soaring Champ DWIGHT HOLLEY IS PROUD TO ANNOUNCE NEW COMPANY TO HELP BOTH BEGINNER & EXPERT FLY INTO THE NEW ERA OF ELECTRIC AIRCRAFT WE ALSO OFFER SELECT FEW PURE SAILPLANES FREE DEMONSTRATION FLIGHTS CHECK OUT UNGlUE TEST FLIGHTS OF YOUR NEW PLANES CALL OR WRITE FOR FREE DESCRIPTIVE FLYER UPS C 00 FOR IMMEDIATE SHIPMENT ELECTRIC KITS IN STOCK AEROBATIC OLOTIMER SPORT SCALE GLIDERS HOLLEYS SILENT FLIGHT 203 748-0083 151 CHESTNUT RIDGE ROAD BETHEL CT 06801 FEATURING ONLY STATE OF THE ART ITEMS 01 51 01 01 n 0 z -I 0 r r 01 01 5 a z vi r m 5 know what mean Now lets talk about what chargers YOU can use system As far know Astros Leisures products capable handling 24 volt input such two 12 volt batteries series will work think Leisure digital chargera very popular productmay used above some limited voltage should check Roland Boucher before try applies whether youre using approach other higher source voltage Also Astros 4005D very popular charger because its built-in adjust ability However please note charger capable handling high input voltage charge just few cells defectits simply intended dissipate several watts its versatile solid state adjust ment circuitry suggest set con trol full click switch rotary control use system will work just fine Also chargers such pictured article 4005D have trickle charge circuit allows small current flow model battery after high-rate charge terminated time switch Astro uses small lamp Leisure small resistor across internal timer contacts components may able tolerate 24 volt input real ly needed purposes anyway Per sonally would simply disconnect such internal parts usually just wired timer screw terminals theres matter some charg ers having large fixed internal resistors particular charging job Leisure charger pictured herein way has switch-selectable resistor use popular RC cars having six seven-cell 12 aH packs resistors simply become resistance complete circuit charging system ordi narily should pose no problem application cannot tolerate add ed resistance simply short resistors out wire jumper Finally charger shown held system baseboard doublesticky-backed Velcro Radio Shack As such easily lifted assembly use usual input output wires have left intact rfo internal modifications have made its perfectly normal device removed environment charge system simple system quite work able very wide range applications theres can done fact Ill presenting deluxe charge system later will based two modified Voltage Inverters supplemented highly-efficient smoothly-adjustable solid state switching mode electronic current-regulator will charge batteries up 30 volts beyond four amps SAILPLANE LAUNCH EQUIPMENT FOR EVERY FIELD $23495 source QUIET FLIGHT Supplies hi-starts electric motors& reducers bat te r aes pa rachu tes tow line drums accessories braided nylon Iinethe PRO PHEY PROPHET 941CURTISS ROBINaL CRATE kits VISA MASTERCARD h EDAVEY EUSYSTEMS m VU CORPORATION ONE WOOD LANEMALVERNPA 19355 215644-6772 Write call information May1985 151 iro Box 10630 Lorain Ohio 44055 APhone 216282-8354 Peanut Scale Models Piper Vigabond Piper Cub 0linsgn 125 utdeor kits nh. $650 Light Indoor kits.. $695 Sport Scale Models 22 Span PC-6 Porter Taylor Craft Stinsan Voyager Rubber CO2 Power PC-B POft&Kits each. $750 Soort Models An Embryo Model 18 Span designed wiol beginners Experts HARD-TO-FIND ITEMS FOR YOUR BUILDING NEEDS Early Bird Tissue br Antique Aircratt S595 True Olde Japanese Tissue 10 3 colors 95 Japanese Tissue 12 6 colors $395 Microlite Plain$325 Silver$395 Microfilm Glue Solvent Condenser Paper 3 sheets 5375 Plan Service over 17 Scale Sport Scale & Peanut Scale Rubber Strip 020 thro 085each 5175 3/32 tliru 5/32each 5195 Winder 61 395 Mark 1161 195 Complete Line 01 Brown CO2 Motors Balsa Wood Outdoor & Indoor Sheets & Strips Add 10% Poutage mum Postage $150 COMPLETE CATALOG 5150 C battery yet Secinied POWRZOOM$36995 RETRBEVER$26495 El S 4 hi 01 01 z 01 a a 201 SE 12thStreeo Pompano Beach FL 33060 305-785-7978 INC TIlE LANOIIIG GEAf eEoPtE Tired kil landing goaro 181 dont III ynar biggie properly o & II Eagineering can salvo yaor problems * CesIum boilt yoor eteds & specs guaranteed III * Strong & durable wiIbslad Ike laugheet aiding * It & Engineering gear will wark & keep yoor biggie flying * Ia clock roplacoineat gear popular models Byron PIlls Christ Eagle CAP 21 gals0 ISA J-3 CUB Air Tack Pawnee Eagle Nosen Big Slick Cbamp Citabria g & g madels Snapper Stinger Seapper Tue 4 THE COMPETITIONS VIEW 'I OF THE WINDSONG I. C, 0 0 N 0 DODGSON DESIGNS 2904 SW CAMANO DRIVE CAMANO ISLAND WA 9825i2J What makes Windsong best plane have deadair lightlift gusting 25 MPH winds thermal contest What makes windsong best plane have x-country race Some say 11to 1 aspect ratio clean solidcore wing no spoiler bays disturb airflow Others say Eppler 214 airfoil combined exclusive full-span camber changing capability including elevator compensated 80 degree flaps reflexible ailerons fact design innovations contribute Windsongs total design concept its unprecedented performance WITH THE WINOSONG THE WHOLE IS TRULY GREATER THAN THE SUM OF ITS PARTS Windsong 19995Camano 15995Pixy 14995 Send 2 stamps catalog VHS video tape too can made readily-avail able materials youll have build some sophisticated electronics make work Please forward questions SASE author Happy Electric Landings Bob Kopski 25 West End Dr Lansdale PA 19446 RC Giant Scale/Beckman Continued page 53 dont miss information con tact Lee Taylor 216 Willow Ave Rose ville CA 95678 phone number 916 783-4190 next have information all-time favorite events STARS Scale Rally Olean NY scheduled July 6 7 year another event limited Giant Scale dont see much else flying site hospitality fantastic place might see Giant Scale aircraft IMAA Fun-Fly Festival IMAA bash year set July 18-21 Mobile AL fifth year event note time change August July Like Nats FFF rotating around different loca tions year like idea since gives IMAA members around country chance participate what Im hearing will another great Im putting weight just reading menus picnic ban quet Yes Mortimer Giant Scalers other things besides fly big birds things eat info available Don Godfrey 91 Blackstone Ave Binghamton NY 13903 telephone 607 724-0115 Bob Beckman 8248 Holly Grove Ct Manassas VA 22110 RC Pylon Racing/Hager Continued page 54 does make wheel pants last longer Well doesnt shock actually destroys wheel pants eliminated attaching land ing gear General Electrics clear bath tub caulking compound assure get proper shock mount slide wheel pant up landing gear place caulking compound backside landing gear pant gear meet Slide back down line up hole gear pant clean unwant ed caulk away Caution Clean out screw hole could lock up wheels install Now assuming final attach ment ie wheel pants painted use Loc-Tite product secure wheels tighten down Allen wrench four-way wrench Place piece vinyl tape over hole unit complete experience using method has nothing convenience factor No special wrench tighten nut easy replacement easy paint touch-up lower-portion damage easy in-field repair replacement longer life wheel pants Hopefully experience will same See next mouth Bill Hager 706 Glen Haven Dr Conroe TX 77385 RC Helicopters/Jolly Continued page 55 really impressed some particular Airtronics 94554 heavyduty servo has proved excellent choice use Helicopter servo features coreless motor ball-bearingsupported output shaft good centering great strength Ive found servo particular value using flybarless rotor system Because heavy feed back loads some servos fail short time have putting lot hours set 94554s prototype GMP flybarless system over last nine months am very satisfied After reading above might think 94554 good flybarless machine quite contrary little thing works well under strenuous en vironment theyre better Bell Hiller system Another product found very useful American RCs new Lok N-Start starting system really dont like starting belts have admit starting cones work fine until starter slips off cone either goes through cabin adds burnished look finish Scale ship So what Lok-N-Start Basically unit consists two parts adapter shaft telescopes over starting shaft machine held place setscrews starter-adap ter another shaft screws onto end starter has Torrington clutch other end Starting accom plished inserting starter over adapter squeezing switch Because Torrington one-way clutch starter cannot keep engine ac celerating once have gotten fire Best off no friction necessary except transferred Torrington very clean simple system should have thought years ago works great months photos addition photo Jack Schultzs coaxial scratchbuilt have scratch-built-fuselage 152 ModelAviation
Edition: Model Aviation - 1985/05
Page Numbers: 50, 51, 148, 149, 150, 151, 152
Radio Control Electrics Bob Kopski CHARGE months column going address most-often-askedabout topics charging particular gonna see make charging system will handle popular motor battery packs system present ed very simple reliable inex pensive can built nearly anybody requires no soldering special tools instruments material can purchased Radio Shack hobby shop hardware auto parts stores Its based something probably already have Astro Leisure similar charger addition well use to see some past lessons Basic Electricity can applied real work ing Electric hardware Lets get charger system pictured consists four main items conventional charger Electric cars planes Voltage Inverter Radio Shack catalog no 22-129 simple resistor bank resistors also Radio Shack some assort ed small items such lamp cord clips ordinary household switch wall box assorted wood pieces some nutz boltz purpose system permit easy charging motor battery pack youre likely find up 14 cells system no longer necessary split up two six-cell seven-cell packs otherwise connected series model make 12-cell 14-cell packs get completely frustrated trying charge ordinary single seven-cell packs grieve no longer answer simple circuit device shown figure unit powered via fairly heavy input cables car battery must connected directly battery posts input 12 volts powers Voltage Inverter turn doubles 12 volts 24 volts capable delivering up three amps output current elevated voltage level very efficient reliable manner have run couple Inverters hours overstressed condition no problems no overheating standard three-way household light switch really single-pole doublethrow switch selects either incoming 12 volt positive line 24 volt positive Voltage Inverter output allocates selection via homemade resistor net works cut voltage steps regular charger Just choose voltage job hand will discussed later resistor bank pictured really pair two distinct resistor sets resistors chosen readily avail able types capable handling just slightly over three amps Thus rated consistent Voltage verter ratings schematic shows resistor bank consists six oneohm 10-watt resistors connected series string series resistors forms 'coarse' currentadjustment device powered switch output arm simpler resistor bank special grouping few resistors powered negative auto battery power input lead serves fine adjustment device resistors mechanically elec trically assembled simple posts consist ing ordinary No 6 No 8 No 10 machine screw hardware normal use resistors will get hot ab solutely necessary assemble resistor banks manner like shown photo will melt solder solder assembled please save yourself trouble way An aluminum foil reflector double-sticky-taped %-in birch plywood resistor plate prevents burning wooden mount 50 Model Aviation Bobs highly-versatile heavy-duty charging system its easily made read column readily-available partseverything mounts 9 13-in 1/4-ln ply base Pro tective cage aluminum window screen material Note cage rails wooden located over resistorsbut over resistor leads Thats because resistors get HOT during charge tube merely holds various chaer cords Photo below gives better idea lead lengthsinput leads doubled lengths No 16 lamp cord wire color-coded light positive dark negative must connected proper terminals car battery Ni-Cd flight pack being recharged drawl ng gives circuit design 1 L SPECIAL NOTE VOLTAGE INVERTER RUNS CONSTANTLY DRAWS VERY LITTLE WHEN 24V POSITION IS NOT IN USE INVERTER IN-LINE FUSE HOLDER RADIO SHACK VOLTAGE BLACK#22129 RED 24V GREEN oJ 12V 3-WAY HOUSEHOLD WALL SWITCH TOP VIEW WIRE N UT 12 0R4-24V SWITCH SELCTED SIXtlA lOW RESISTORS RADIO SHACK #271-131 OHMS 0 2 3 4 5 6 0 1/4 RED 0 OLK 0~~~1 vW 3/4 TOP VIEW RESISTOR ASSEMBLY DOTTED WIRING BOTTOM SIDE FOUR O47n SW LARGE AUTORESISTORS ERY CLIPSRADIO SHACK *271130 TO MOTOR BATTERYCHARGER simple cover screen made ordi nary household aluminum door screen epoxied wooden rails prevents acciden tal contact hot resistors two resistor banks have multiple-output taps various individual resistor intersections screw posts become input connections charger clip leads connected red positive charger clip lead connect ed seven coarse positive resistor screw posts black negative charger clip lead goes remaining four fine negative screw 'posts' conventional charger output con nector plugs model battery pack other aspects its operation remain normal except some small points made later Thus charg er timer switch used before charger current meter used before fact familiar meter strument youll need know thing working OK Now some words about works past two columns Basic Electricity installments know current circuit determined available voltage divided cir cuit resistance also know voltage charging sourcethe auto batteryis ordinarily 12 volts fact can does vary somewhat over somewhat under 12 volts 24 volt Inverter output will follow input variation Also know model power-system battery being Ni-Cd dis plays fairly predictable terminal voltage too has some variation around nominal point basic importance understand what meant available circuit voltage schematic consistent familiar practice obvious model battery can charged source voltage greater two Thus familiar example six-cell NiContinued page 148 Twin resistor bank 1 mounts 5 x 7 piece hIn birch piy Note aluminum foil heatrefiector Four resistors ieft 047 ohm posts 27k-in centers Larger resistors ohm mounted 3-in centers DO NOT SOLDER THE LEADS TO THE POSTSthe joints might meit servicel Wiring backside resistor bank iooks ilke Center Use No 16 No 18 Wirestranded soi id soiid easier handie Note wiring smaii resistors bottom wires simple series Detali shot R resistor bank shows use brightpiated 632 machine screws nuts washers lock washers Screws 1 1A long spaced /z span aiiow resistor bodies bunch upthey must remain separated proper cooling May1985 51 WIRE NUT 5-6 16 GAUGE LAMP CORD PAIRS inside switch boxwire nuts used connect everything Switch screws near side connected red output iead Voltage inverter L other R goes positive resistor set hidden back switch ties car batterys posi tive input cabie black fused lead Voltage Inverter Note strain relief cable clamp discussed quite few club newsletters subject noise mufflers Most about necessity improve noise situation using better mufflers Almost club Ive involved last 15 years least formal muffler rule Some quite specific Nowadays almost everyone uses mufflers engines However middle Sixties almost nobody used Engines loud muffler propo nents claimed use mufflers would guarantee against loss fly ing field due noise problems early mufflers did lot quiet engines expense losing lot power Modern mufflers good job reduc ing noise sacrificing power remember thinking time club Western Ohio Radio Kontrol Socie ty required use mufflers about 1967 question time before everyone would forget what like before started using mufflers noise complaints would start again As know situation upon us As much hate think unless dra matic new improvements made mufflers two-cycle engines lot flying fields will lost other alternative can see clubs noise problems ban two-cycle engines favor four-cycle engines thats done wonder long will take flying field neighbors forget before four-cycle engines required start complaining again second item Id like share club newsletters pub lished Mount Rainier Radio Con trol Society Newsletter Tacoma WA Its semi-anonymous author Bill D wrote Old Threat Finally Identified Field Psychologist Glitchus Crashemup commonly known glitch has finally identified after years research dread malady preys upon certain segment species Homo Sapiens known RC Pilots normally lurking open fields grown men play model air craft glitch very dangerous full plumage adult male should approached experienced glitch hunters wielding loaded field strength meters has bite produces im mediate reactions beginning ner vous shaking twitching thumbs sequence symptoms often followed cries dont have Splintering thudding noises occur almost immediately point vic tim usually lapses depression may become militant approached next few minutes glitch invisible real imagined experience enemy should reported immediate ly field psychologist Ron Van Putte 111 Sleepy Oaks Rd Ft Walton Beach FL 32548 RC Electrics/Kopski Continued page 51 Cd will under charge eventually reach voltage its terminals equal about 15 x 6 about nine volts since Ni-Cds float up 15 volts per cell under charge take source volt age auto battery 12 volts avail able circuit voltage simply three volts difference 12 nine volts voltage appears across charging circuit resistance ear lier lessons circuit current charg ing current established choosing suitable resistor charge system design has plenty resistors choose Lets figure out make choice Last month saw several ways write Ohms Law Youll remember law relates three common elec trical terms voltage V current resistance R particular saw resistance can found dividing available circuit voltage ACV cir cuit current like R As example lets say six-cell pack made up 800 MAh cells Three amps very good charge current use 148 Model Aviation -I A monthly publication covering International RC Soaring Scene $1 6/yr US Canada & Mexico $24/yr elsewhere via airmail Post Office Box 269 Peterborough NH 03458 convenient Thus R lts divided 3 amps 1 ohm Clearly have connect charger clip leads resistor posts total resistance tapped off ohm could simply put black lead negative 0 ohms post red lead positive 1 ohm tap thats just sure everything OK simply note charger ammeter reading dial up timer switch should now clear what have really same old charger used using now choice supply voltages very convenient set selectable resistors fact no need go through arithmetic shown above practice just select desired source voltage switch connect charger input leads two resistor sets point highest resistance lowest current connect model battery start timer switch check ammeter reading Move clip leads lower values resistance increase charge current value desired over three amps An effective procedure arriving needed resistance start both high resistance taps move through coarse set steps ohm until youre close tobut low sideof desired current move through fine steps fine tune desired value can motor bat tery up 14 cells further note practical nature charging current will gradually decrease during time required charge because terminal voltage model pack will slowly rise available circuit voltage voltage across chosen resistor will decrease could just keep changing taps its necessary After two uses will become clear much current drop will can simply start little above desired value because know cur rent will slowly drop below its average current thats important provid ed variation too great similar vein car battery will gradually lower its voltage during busy day flying taps used earlier day will ones chosen later beauty design should always able ad just good charge Now lets examine special frustrating case seven-cell system read ers have told trouble exper ience getting good charge such motor pack Following six-cell example above can see sevencell pack will climb total voltage Signal Guard blocks random noise oft-frequency signals can cause loss control air land RC models Signal Guard responds sig nals its own precisely tuned fre quency ignoring static noise craft itself Plus additional amplification allows control operators visual limit Special Introductory Offer 87w about 15 x 7 105 voltsor moreas charge progresses 12 volt auto battery available circuit voltage 12 15 volts Obviously small voltage requires very small circuit resistance attain reasonable charg ing current Its under conditions things like good battery-clip contact good charger connection model power system extremely importantand also often unreliable beginning charge battery voltage relatively low say about 12 x 7 84 volts available circuit voltage 12 6 volts Thus beginning charge later ACV varies over 21and would charge want spend time flying less time money repairing crashed model Signal Guard answer Call toll-free 1-800-468-8215 order Signal Guard TM major credit card send $150 check money order Thlls PO Box 30179 Portland OR 97230 Oregon call collect 503-257-0912 current given circuit resistance Thus typical seven-cell pack 12 volt supply can have both unreliable circuit resistance highly variable ACV together can result very questionable charge course charge system shown least allows easy adjustment current-controlling taps theres better approach problem system presented can very good job charging seven-cell packs switching 24 volt position tap ping off enough resistance establish desired current two example bat tery voltages mentioned above ACV would 24 135 24 156 volts respectively May1985 149 90 day warranty. Selected dealerships available variation case clearly very small thus charge current will much constant Also selected resis tance will over four ohmsmuch would used above much stable forgiving contact resis tance variation Thus excellent charge available seven-cell packs should clear discussions above can generalized number cells fact smaller number cells model battery controlled charge con versely smaller ACV un reliable charge As rule thumb suggest using 12 volt position six fewer cells 24 volt option seven cells Naturally charging 14 cells will worst case regard possible use 24 volts time can fact almost left out 12/24 switch just used 24 volt Voltage Inverter output However considera tion highlights two known disadvantages charge system may relatively inefficient depending its used charging techniques use~ power auto battery needed charge model battery wasted power appearsyou guessed itas heat waste larger greater ACV Therefore some may consider prudent use lower two available source voltages possi ble Also lower-voltage position necessary have very small packs such small-capacity two three fourcell configurations As side point interest power wasted heat other charg er really no big deal should annoyance Consider common household 60 watt light bulb Surely no would wrap hand around thats few minutesits hot purpose light bulb provide light heat Only very small amount con sumed electrical power ever makes its way form light energyits virtual ly wasted heat Thus com mon light bulb very inefficient device second disadvantage charge system previously-mentioned threeamp limit Remember limit imposed Voltage Inverter specifica tion choice resistors Lets apply some Basic Electricity illus trate latter point resistors used Radio Shack 10 watt components description much power can safely dissi pate heat Last month learned power resistor such flashlight lamp discussed equal x x R case know resis tance Lets pick ohm resistor know power ratingits 10 watts two pieces information can find maximum current allowed thus P R Pxl0 atts rewriting 12 = 10 1 i/i3l6 amps example can see use fulness having some knowledge basic electricity back disadvantage itself As mentioned earlier three amps very convenient current charging 800 mali cells what use Thats because charger timer switches 15-minute clocks 3 amps x 15 minutes 45 ampminutes 4500% mAh just little short label capacity cells question represents safe charge put nearly-dead pack what about 12 Ah cells Well takes three amps about 12/3 x 60 24 minutes reach label capacity would charge about 20 minutes perfectly safe carefree charge dead Thus disadvantage have charge 12 Ah packs 15 minutes dial five timer other hand much better getting questionable charge some other less-controlled way have down path will SAILPLANES WORLD iSOlA Coffee Rd Modesto CA 95355 Sailplanes International Krause MultiPlex Wanitschek Wik & Roke Sport-Scale-F3B European Hardware Accessories Send $500 Cat & Price List 209 577-0506 IntducIng. Ereb cr11 RIC Idle-Bar Glow Plugs Long Short Also.Only $169 Traditional line non-idle bar Glow Plugs Six Types 3 Heat Ranges High Performance Glow Element Blow Proof Seal Only I Swanson Associates_ PO Box 151 e NJ 07470 5/Mi ______ 150 Model Aviation ELECTRIC MODEL & SAILPLANE SPECIALISTS 1981 World Soaring Champ DWIGHT HOLLEY IS PROUD TO ANNOUNCE NEW COMPANY TO HELP BOTH BEGINNER & EXPERT FLY INTO THE NEW ERA OF ELECTRIC AIRCRAFT WE ALSO OFFER SELECT FEW PURE SAILPLANES FREE DEMONSTRATION FLIGHTS CHECK OUT UNGlUE TEST FLIGHTS OF YOUR NEW PLANES CALL OR WRITE FOR FREE DESCRIPTIVE FLYER UPS C 00 FOR IMMEDIATE SHIPMENT ELECTRIC KITS IN STOCK AEROBATIC OLOTIMER SPORT SCALE GLIDERS HOLLEYS SILENT FLIGHT 203 748-0083 151 CHESTNUT RIDGE ROAD BETHEL CT 06801 FEATURING ONLY STATE OF THE ART ITEMS 01 51 01 01 n 0 z -I 0 r r 01 01 5 a z vi r m 5 know what mean Now lets talk about what chargers YOU can use system As far know Astros Leisures products capable handling 24 volt input such two 12 volt batteries series will work think Leisure digital chargera very popular productmay used above some limited voltage should check Roland Boucher before try applies whether youre using approach other higher source voltage Also Astros 4005D very popular charger because its built-in adjust ability However please note charger capable handling high input voltage charge just few cells defectits simply intended dissipate several watts its versatile solid state adjust ment circuitry suggest set con trol full click switch rotary control use system will work just fine Also chargers such pictured article 4005D have trickle charge circuit allows small current flow model battery after high-rate charge terminated time switch Astro uses small lamp Leisure small resistor across internal timer contacts components may able tolerate 24 volt input real ly needed purposes anyway Per sonally would simply disconnect such internal parts usually just wired timer screw terminals theres matter some charg ers having large fixed internal resistors particular charging job Leisure charger pictured herein way has switch-selectable resistor use popular RC cars having six seven-cell 12 aH packs resistors simply become resistance complete circuit charging system ordi narily should pose no problem application cannot tolerate add ed resistance simply short resistors out wire jumper Finally charger shown held system baseboard doublesticky-backed Velcro Radio Shack As such easily lifted assembly use usual input output wires have left intact rfo internal modifications have made its perfectly normal device removed environment charge system simple system quite work able very wide range applications theres can done fact Ill presenting deluxe charge system later will based two modified Voltage Inverters supplemented highly-efficient smoothly-adjustable solid state switching mode electronic current-regulator will charge batteries up 30 volts beyond four amps SAILPLANE LAUNCH EQUIPMENT FOR EVERY FIELD $23495 source QUIET FLIGHT Supplies hi-starts electric motors& reducers bat te r aes pa rachu tes tow line drums accessories braided nylon Iinethe PRO PHEY PROPHET 941CURTISS ROBINaL CRATE kits VISA MASTERCARD h EDAVEY EUSYSTEMS m VU CORPORATION ONE WOOD LANEMALVERNPA 19355 215644-6772 Write call information May1985 151 iro Box 10630 Lorain Ohio 44055 APhone 216282-8354 Peanut Scale Models Piper Vigabond Piper Cub 0linsgn 125 utdeor kits nh. $650 Light Indoor kits.. $695 Sport Scale Models 22 Span PC-6 Porter Taylor Craft Stinsan Voyager Rubber CO2 Power PC-B POft&Kits each. $750 Soort Models An Embryo Model 18 Span designed wiol beginners Experts HARD-TO-FIND ITEMS FOR YOUR BUILDING NEEDS Early Bird Tissue br Antique Aircratt S595 True Olde Japanese Tissue 10 3 colors 95 Japanese Tissue 12 6 colors $395 Microlite Plain$325 Silver$395 Microfilm Glue Solvent Condenser Paper 3 sheets 5375 Plan Service over 17 Scale Sport Scale & Peanut Scale Rubber Strip 020 thro 085each 5175 3/32 tliru 5/32each 5195 Winder 61 395 Mark 1161 195 Complete Line 01 Brown CO2 Motors Balsa Wood Outdoor & Indoor Sheets & Strips Add 10% Poutage mum Postage $150 COMPLETE CATALOG 5150 C battery yet Secinied POWRZOOM$36995 RETRBEVER$26495 El S 4 hi 01 01 z 01 a a 201 SE 12thStreeo Pompano Beach FL 33060 305-785-7978 INC TIlE LANOIIIG GEAf eEoPtE Tired kil landing goaro 181 dont III ynar biggie properly o & II Eagineering can salvo yaor problems * CesIum boilt yoor eteds & specs guaranteed III * Strong & durable wiIbslad Ike laugheet aiding * It & Engineering gear will wark & keep yoor biggie flying * Ia clock roplacoineat gear popular models Byron PIlls Christ Eagle CAP 21 gals0 ISA J-3 CUB Air Tack Pawnee Eagle Nosen Big Slick Cbamp Citabria g & g madels Snapper Stinger Seapper Tue 4 THE COMPETITIONS VIEW 'I OF THE WINDSONG I. C, 0 0 N 0 DODGSON DESIGNS 2904 SW CAMANO DRIVE CAMANO ISLAND WA 9825i2J What makes Windsong best plane have deadair lightlift gusting 25 MPH winds thermal contest What makes windsong best plane have x-country race Some say 11to 1 aspect ratio clean solidcore wing no spoiler bays disturb airflow Others say Eppler 214 airfoil combined exclusive full-span camber changing capability including elevator compensated 80 degree flaps reflexible ailerons fact design innovations contribute Windsongs total design concept its unprecedented performance WITH THE WINOSONG THE WHOLE IS TRULY GREATER THAN THE SUM OF ITS PARTS Windsong 19995Camano 15995Pixy 14995 Send 2 stamps catalog VHS video tape too can made readily-avail able materials youll have build some sophisticated electronics make work Please forward questions SASE author Happy Electric Landings Bob Kopski 25 West End Dr Lansdale PA 19446 RC Giant Scale/Beckman Continued page 53 dont miss information con tact Lee Taylor 216 Willow Ave Rose ville CA 95678 phone number 916 783-4190 next have information all-time favorite events STARS Scale Rally Olean NY scheduled July 6 7 year another event limited Giant Scale dont see much else flying site hospitality fantastic place might see Giant Scale aircraft IMAA Fun-Fly Festival IMAA bash year set July 18-21 Mobile AL fifth year event note time change August July Like Nats FFF rotating around different loca tions year like idea since gives IMAA members around country chance participate what Im hearing will another great Im putting weight just reading menus picnic ban quet Yes Mortimer Giant Scalers other things besides fly big birds things eat info available Don Godfrey 91 Blackstone Ave Binghamton NY 13903 telephone 607 724-0115 Bob Beckman 8248 Holly Grove Ct Manassas VA 22110 RC Pylon Racing/Hager Continued page 54 does make wheel pants last longer Well doesnt shock actually destroys wheel pants eliminated attaching land ing gear General Electrics clear bath tub caulking compound assure get proper shock mount slide wheel pant up landing gear place caulking compound backside landing gear pant gear meet Slide back down line up hole gear pant clean unwant ed caulk away Caution Clean out screw hole could lock up wheels install Now assuming final attach ment ie wheel pants painted use Loc-Tite product secure wheels tighten down Allen wrench four-way wrench Place piece vinyl tape over hole unit complete experience using method has nothing convenience factor No special wrench tighten nut easy replacement easy paint touch-up lower-portion damage easy in-field repair replacement longer life wheel pants Hopefully experience will same See next mouth Bill Hager 706 Glen Haven Dr Conroe TX 77385 RC Helicopters/Jolly Continued page 55 really impressed some particular Airtronics 94554 heavyduty servo has proved excellent choice use Helicopter servo features coreless motor ball-bearingsupported output shaft good centering great strength Ive found servo particular value using flybarless rotor system Because heavy feed back loads some servos fail short time have putting lot hours set 94554s prototype GMP flybarless system over last nine months am very satisfied After reading above might think 94554 good flybarless machine quite contrary little thing works well under strenuous en vironment theyre better Bell Hiller system Another product found very useful American RCs new Lok N-Start starting system really dont like starting belts have admit starting cones work fine until starter slips off cone either goes through cabin adds burnished look finish Scale ship So what Lok-N-Start Basically unit consists two parts adapter shaft telescopes over starting shaft machine held place setscrews starter-adap ter another shaft screws onto end starter has Torrington clutch other end Starting accom plished inserting starter over adapter squeezing switch Because Torrington one-way clutch starter cannot keep engine ac celerating once have gotten fire Best off no friction necessary except transferred Torrington very clean simple system should have thought years ago works great months photos addition photo Jack Schultzs coaxial scratchbuilt have scratch-built-fuselage 152 ModelAviation
Edition: Model Aviation - 1985/05
Page Numbers: 50, 51, 148, 149, 150, 151, 152
Radio Control Electrics Bob Kopski CHARGE months column going address most-often-askedabout topics charging particular gonna see make charging system will handle popular motor battery packs system present ed very simple reliable inex pensive can built nearly anybody requires no soldering special tools instruments material can purchased Radio Shack hobby shop hardware auto parts stores Its based something probably already have Astro Leisure similar charger addition well use to see some past lessons Basic Electricity can applied real work ing Electric hardware Lets get charger system pictured consists four main items conventional charger Electric cars planes Voltage Inverter Radio Shack catalog no 22-129 simple resistor bank resistors also Radio Shack some assort ed small items such lamp cord clips ordinary household switch wall box assorted wood pieces some nutz boltz purpose system permit easy charging motor battery pack youre likely find up 14 cells system no longer necessary split up two six-cell seven-cell packs otherwise connected series model make 12-cell 14-cell packs get completely frustrated trying charge ordinary single seven-cell packs grieve no longer answer simple circuit device shown figure unit powered via fairly heavy input cables car battery must connected directly battery posts input 12 volts powers Voltage Inverter turn doubles 12 volts 24 volts capable delivering up three amps output current elevated voltage level very efficient reliable manner have run couple Inverters hours overstressed condition no problems no overheating standard three-way household light switch really single-pole doublethrow switch selects either incoming 12 volt positive line 24 volt positive Voltage Inverter output allocates selection via homemade resistor net works cut voltage steps regular charger Just choose voltage job hand will discussed later resistor bank pictured really pair two distinct resistor sets resistors chosen readily avail able types capable handling just slightly over three amps Thus rated consistent Voltage verter ratings schematic shows resistor bank consists six oneohm 10-watt resistors connected series string series resistors forms 'coarse' currentadjustment device powered switch output arm simpler resistor bank special grouping few resistors powered negative auto battery power input lead serves fine adjustment device resistors mechanically elec trically assembled simple posts consist ing ordinary No 6 No 8 No 10 machine screw hardware normal use resistors will get hot ab solutely necessary assemble resistor banks manner like shown photo will melt solder solder assembled please save yourself trouble way An aluminum foil reflector double-sticky-taped %-in birch plywood resistor plate prevents burning wooden mount 50 Model Aviation Bobs highly-versatile heavy-duty charging system its easily made read column readily-available partseverything mounts 9 13-in 1/4-ln ply base Pro tective cage aluminum window screen material Note cage rails wooden located over resistorsbut over resistor leads Thats because resistors get HOT during charge tube merely holds various chaer cords Photo below gives better idea lead lengthsinput leads doubled lengths No 16 lamp cord wire color-coded light positive dark negative must connected proper terminals car battery Ni-Cd flight pack being recharged drawl ng gives circuit design 1 L SPECIAL NOTE VOLTAGE INVERTER RUNS CONSTANTLY DRAWS VERY LITTLE WHEN 24V POSITION IS NOT IN USE INVERTER IN-LINE FUSE HOLDER RADIO SHACK VOLTAGE BLACK#22129 RED 24V GREEN oJ 12V 3-WAY HOUSEHOLD WALL SWITCH TOP VIEW WIRE N UT 12 0R4-24V SWITCH SELCTED SIXtlA lOW RESISTORS RADIO SHACK #271-131 OHMS 0 2 3 4 5 6 0 1/4 RED 0 OLK 0~~~1 vW 3/4 TOP VIEW RESISTOR ASSEMBLY DOTTED WIRING BOTTOM SIDE FOUR O47n SW LARGE AUTORESISTORS ERY CLIPSRADIO SHACK *271130 TO MOTOR BATTERYCHARGER simple cover screen made ordi nary household aluminum door screen epoxied wooden rails prevents acciden tal contact hot resistors two resistor banks have multiple-output taps various individual resistor intersections screw posts become input connections charger clip leads connected red positive charger clip lead connect ed seven coarse positive resistor screw posts black negative charger clip lead goes remaining four fine negative screw 'posts' conventional charger output con nector plugs model battery pack other aspects its operation remain normal except some small points made later Thus charg er timer switch used before charger current meter used before fact familiar meter strument youll need know thing working OK Now some words about works past two columns Basic Electricity installments know current circuit determined available voltage divided cir cuit resistance also know voltage charging sourcethe auto batteryis ordinarily 12 volts fact can does vary somewhat over somewhat under 12 volts 24 volt Inverter output will follow input variation Also know model power-system battery being Ni-Cd dis plays fairly predictable terminal voltage too has some variation around nominal point basic importance understand what meant available circuit voltage schematic consistent familiar practice obvious model battery can charged source voltage greater two Thus familiar example six-cell NiContinued page 148 Twin resistor bank 1 mounts 5 x 7 piece hIn birch piy Note aluminum foil heatrefiector Four resistors ieft 047 ohm posts 27k-in centers Larger resistors ohm mounted 3-in centers DO NOT SOLDER THE LEADS TO THE POSTSthe joints might meit servicel Wiring backside resistor bank iooks ilke Center Use No 16 No 18 Wirestranded soi id soiid easier handie Note wiring smaii resistors bottom wires simple series Detali shot R resistor bank shows use brightpiated 632 machine screws nuts washers lock washers Screws 1 1A long spaced /z span aiiow resistor bodies bunch upthey must remain separated proper cooling May1985 51 WIRE NUT 5-6 16 GAUGE LAMP CORD PAIRS inside switch boxwire nuts used connect everything Switch screws near side connected red output iead Voltage inverter L other R goes positive resistor set hidden back switch ties car batterys posi tive input cabie black fused lead Voltage Inverter Note strain relief cable clamp discussed quite few club newsletters subject noise mufflers Most about necessity improve noise situation using better mufflers Almost club Ive involved last 15 years least formal muffler rule Some quite specific Nowadays almost everyone uses mufflers engines However middle Sixties almost nobody used Engines loud muffler propo nents claimed use mufflers would guarantee against loss fly ing field due noise problems early mufflers did lot quiet engines expense losing lot power Modern mufflers good job reduc ing noise sacrificing power remember thinking time club Western Ohio Radio Kontrol Socie ty required use mufflers about 1967 question time before everyone would forget what like before started using mufflers noise complaints would start again As know situation upon us As much hate think unless dra matic new improvements made mufflers two-cycle engines lot flying fields will lost other alternative can see clubs noise problems ban two-cycle engines favor four-cycle engines thats done wonder long will take flying field neighbors forget before four-cycle engines required start complaining again second item Id like share club newsletters pub lished Mount Rainier Radio Con trol Society Newsletter Tacoma WA Its semi-anonymous author Bill D wrote Old Threat Finally Identified Field Psychologist Glitchus Crashemup commonly known glitch has finally identified after years research dread malady preys upon certain segment species Homo Sapiens known RC Pilots normally lurking open fields grown men play model air craft glitch very dangerous full plumage adult male should approached experienced glitch hunters wielding loaded field strength meters has bite produces im mediate reactions beginning ner vous shaking twitching thumbs sequence symptoms often followed cries dont have Splintering thudding noises occur almost immediately point vic tim usually lapses depression may become militant approached next few minutes glitch invisible real imagined experience enemy should reported immediate ly field psychologist Ron Van Putte 111 Sleepy Oaks Rd Ft Walton Beach FL 32548 RC Electrics/Kopski Continued page 51 Cd will under charge eventually reach voltage its terminals equal about 15 x 6 about nine volts since Ni-Cds float up 15 volts per cell under charge take source volt age auto battery 12 volts avail able circuit voltage simply three volts difference 12 nine volts voltage appears across charging circuit resistance ear lier lessons circuit current charg ing current established choosing suitable resistor charge system design has plenty resistors choose Lets figure out make choice Last month saw several ways write Ohms Law Youll remember law relates three common elec trical terms voltage V current resistance R particular saw resistance can found dividing available circuit voltage ACV cir cuit current like R As example lets say six-cell pack made up 800 MAh cells Three amps very good charge current use 148 Model Aviation -I A monthly publication covering International RC Soaring Scene $1 6/yr US Canada & Mexico $24/yr elsewhere via airmail Post Office Box 269 Peterborough NH 03458 convenient Thus R lts divided 3 amps 1 ohm Clearly have connect charger clip leads resistor posts total resistance tapped off ohm could simply put black lead negative 0 ohms post red lead positive 1 ohm tap thats just sure everything OK simply note charger ammeter reading dial up timer switch should now clear what have really same old charger used using now choice supply voltages very convenient set selectable resistors fact no need go through arithmetic shown above practice just select desired source voltage switch connect charger input leads two resistor sets point highest resistance lowest current connect model battery start timer switch check ammeter reading Move clip leads lower values resistance increase charge current value desired over three amps An effective procedure arriving needed resistance start both high resistance taps move through coarse set steps ohm until youre close tobut low sideof desired current move through fine steps fine tune desired value can motor bat tery up 14 cells further note practical nature charging current will gradually decrease during time required charge because terminal voltage model pack will slowly rise available circuit voltage voltage across chosen resistor will decrease could just keep changing taps its necessary After two uses will become clear much current drop will can simply start little above desired value because know cur rent will slowly drop below its average current thats important provid ed variation too great similar vein car battery will gradually lower its voltage during busy day flying taps used earlier day will ones chosen later beauty design should always able ad just good charge Now lets examine special frustrating case seven-cell system read ers have told trouble exper ience getting good charge such motor pack Following six-cell example above can see sevencell pack will climb total voltage Signal Guard blocks random noise oft-frequency signals can cause loss control air land RC models Signal Guard responds sig nals its own precisely tuned fre quency ignoring static noise craft itself Plus additional amplification allows control operators visual limit Special Introductory Offer 87w about 15 x 7 105 voltsor moreas charge progresses 12 volt auto battery available circuit voltage 12 15 volts Obviously small voltage requires very small circuit resistance attain reasonable charg ing current Its under conditions things like good battery-clip contact good charger connection model power system extremely importantand also often unreliable beginning charge battery voltage relatively low say about 12 x 7 84 volts available circuit voltage 12 6 volts Thus beginning charge later ACV varies over 21and would charge want spend time flying less time money repairing crashed model Signal Guard answer Call toll-free 1-800-468-8215 order Signal Guard TM major credit card send $150 check money order Thlls PO Box 30179 Portland OR 97230 Oregon call collect 503-257-0912 current given circuit resistance Thus typical seven-cell pack 12 volt supply can have both unreliable circuit resistance highly variable ACV together can result very questionable charge course charge system shown least allows easy adjustment current-controlling taps theres better approach problem system presented can very good job charging seven-cell packs switching 24 volt position tap ping off enough resistance establish desired current two example bat tery voltages mentioned above ACV would 24 135 24 156 volts respectively May1985 149 90 day warranty. Selected dealerships available variation case clearly very small thus charge current will much constant Also selected resis tance will over four ohmsmuch would used above much stable forgiving contact resis tance variation Thus excellent charge available seven-cell packs should clear discussions above can generalized number cells fact smaller number cells model battery controlled charge con versely smaller ACV un reliable charge As rule thumb suggest using 12 volt position six fewer cells 24 volt option seven cells Naturally charging 14 cells will worst case regard possible use 24 volts time can fact almost left out 12/24 switch just used 24 volt Voltage Inverter output However considera tion highlights two known disadvantages charge system may relatively inefficient depending its used charging techniques use~ power auto battery needed charge model battery wasted power appearsyou guessed itas heat waste larger greater ACV Therefore some may consider prudent use lower two available source voltages possi ble Also lower-voltage position necessary have very small packs such small-capacity two three fourcell configurations As side point interest power wasted heat other charg er really no big deal should annoyance Consider common household 60 watt light bulb Surely no would wrap hand around thats few minutesits hot purpose light bulb provide light heat Only very small amount con sumed electrical power ever makes its way form light energyits virtual ly wasted heat Thus com mon light bulb very inefficient device second disadvantage charge system previously-mentioned threeamp limit Remember limit imposed Voltage Inverter specifica tion choice resistors Lets apply some Basic Electricity illus trate latter point resistors used Radio Shack 10 watt components description much power can safely dissi pate heat Last month learned power resistor such flashlight lamp discussed equal x x R case know resis tance Lets pick ohm resistor know power ratingits 10 watts two pieces information can find maximum current allowed thus P R Pxl0 atts rewriting 12 = 10 1 i/i3l6 amps example can see use fulness having some knowledge basic electricity back disadvantage itself As mentioned earlier three amps very convenient current charging 800 mali cells what use Thats because charger timer switches 15-minute clocks 3 amps x 15 minutes 45 ampminutes 4500% mAh just little short label capacity cells question represents safe charge put nearly-dead pack what about 12 Ah cells Well takes three amps about 12/3 x 60 24 minutes reach label capacity would charge about 20 minutes perfectly safe carefree charge dead Thus disadvantage have charge 12 Ah packs 15 minutes dial five timer other hand much better getting questionable charge some other less-controlled way have down path will SAILPLANES WORLD iSOlA Coffee Rd Modesto CA 95355 Sailplanes International Krause MultiPlex Wanitschek Wik & Roke Sport-Scale-F3B European Hardware Accessories Send $500 Cat & Price List 209 577-0506 IntducIng. Ereb cr11 RIC Idle-Bar Glow Plugs Long Short Also.Only $169 Traditional line non-idle bar Glow Plugs Six Types 3 Heat Ranges High Performance Glow Element Blow Proof Seal Only I Swanson Associates_ PO Box 151 e NJ 07470 5/Mi ______ 150 Model Aviation ELECTRIC MODEL & SAILPLANE SPECIALISTS 1981 World Soaring Champ DWIGHT HOLLEY IS PROUD TO ANNOUNCE NEW COMPANY TO HELP BOTH BEGINNER & EXPERT FLY INTO THE NEW ERA OF ELECTRIC AIRCRAFT WE ALSO OFFER SELECT FEW PURE SAILPLANES FREE DEMONSTRATION FLIGHTS CHECK OUT UNGlUE TEST FLIGHTS OF YOUR NEW PLANES CALL OR WRITE FOR FREE DESCRIPTIVE FLYER UPS C 00 FOR IMMEDIATE SHIPMENT ELECTRIC KITS IN STOCK AEROBATIC OLOTIMER SPORT SCALE GLIDERS HOLLEYS SILENT FLIGHT 203 748-0083 151 CHESTNUT RIDGE ROAD BETHEL CT 06801 FEATURING ONLY STATE OF THE ART ITEMS 01 51 01 01 n 0 z -I 0 r r 01 01 5 a z vi r m 5 know what mean Now lets talk about what chargers YOU can use system As far know Astros Leisures products capable handling 24 volt input such two 12 volt batteries series will work think Leisure digital chargera very popular productmay used above some limited voltage should check Roland Boucher before try applies whether youre using approach other higher source voltage Also Astros 4005D very popular charger because its built-in adjust ability However please note charger capable handling high input voltage charge just few cells defectits simply intended dissipate several watts its versatile solid state adjust ment circuitry suggest set con trol full click switch rotary control use system will work just fine Also chargers such pictured article 4005D have trickle charge circuit allows small current flow model battery after high-rate charge terminated time switch Astro uses small lamp Leisure small resistor across internal timer contacts components may able tolerate 24 volt input real ly needed purposes anyway Per sonally would simply disconnect such internal parts usually just wired timer screw terminals theres matter some charg ers having large fixed internal resistors particular charging job Leisure charger pictured herein way has switch-selectable resistor use popular RC cars having six seven-cell 12 aH packs resistors simply become resistance complete circuit charging system ordi narily should pose no problem application cannot tolerate add ed resistance simply short resistors out wire jumper Finally charger shown held system baseboard doublesticky-backed Velcro Radio Shack As such easily lifted assembly use usual input output wires have left intact rfo internal modifications have made its perfectly normal device removed environment charge system simple system quite work able very wide range applications theres can done fact Ill presenting deluxe charge system later will based two modified Voltage Inverters supplemented highly-efficient smoothly-adjustable solid state switching mode electronic current-regulator will charge batteries up 30 volts beyond four amps SAILPLANE LAUNCH EQUIPMENT FOR EVERY FIELD $23495 source QUIET FLIGHT Supplies hi-starts electric motors& reducers bat te r aes pa rachu tes tow line drums accessories braided nylon Iinethe PRO PHEY PROPHET 941CURTISS ROBINaL CRATE kits VISA MASTERCARD h EDAVEY EUSYSTEMS m VU CORPORATION ONE WOOD LANEMALVERNPA 19355 215644-6772 Write call information May1985 151 iro Box 10630 Lorain Ohio 44055 APhone 216282-8354 Peanut Scale Models Piper Vigabond Piper Cub 0linsgn 125 utdeor kits nh. $650 Light Indoor kits.. $695 Sport Scale Models 22 Span PC-6 Porter Taylor Craft Stinsan Voyager Rubber CO2 Power PC-B POft&Kits each. $750 Soort Models An Embryo Model 18 Span designed wiol beginners Experts HARD-TO-FIND ITEMS FOR YOUR BUILDING NEEDS Early Bird Tissue br Antique Aircratt S595 True Olde Japanese Tissue 10 3 colors 95 Japanese Tissue 12 6 colors $395 Microlite Plain$325 Silver$395 Microfilm Glue Solvent Condenser Paper 3 sheets 5375 Plan Service over 17 Scale Sport Scale & Peanut Scale Rubber Strip 020 thro 085each 5175 3/32 tliru 5/32each 5195 Winder 61 395 Mark 1161 195 Complete Line 01 Brown CO2 Motors Balsa Wood Outdoor & Indoor Sheets & Strips Add 10% Poutage mum Postage $150 COMPLETE CATALOG 5150 C battery yet Secinied POWRZOOM$36995 RETRBEVER$26495 El S 4 hi 01 01 z 01 a a 201 SE 12thStreeo Pompano Beach FL 33060 305-785-7978 INC TIlE LANOIIIG GEAf eEoPtE Tired kil landing goaro 181 dont III ynar biggie properly o & II Eagineering can salvo yaor problems * CesIum boilt yoor eteds & specs guaranteed III * Strong & durable wiIbslad Ike laugheet aiding * It & Engineering gear will wark & keep yoor biggie flying * Ia clock roplacoineat gear popular models Byron PIlls Christ Eagle CAP 21 gals0 ISA J-3 CUB Air Tack Pawnee Eagle Nosen Big Slick Cbamp Citabria g & g madels Snapper Stinger Seapper Tue 4 THE COMPETITIONS VIEW 'I OF THE WINDSONG I. C, 0 0 N 0 DODGSON DESIGNS 2904 SW CAMANO DRIVE CAMANO ISLAND WA 9825i2J What makes Windsong best plane have deadair lightlift gusting 25 MPH winds thermal contest What makes windsong best plane have x-country race Some say 11to 1 aspect ratio clean solidcore wing no spoiler bays disturb airflow Others say Eppler 214 airfoil combined exclusive full-span camber changing capability including elevator compensated 80 degree flaps reflexible ailerons fact design innovations contribute Windsongs total design concept its unprecedented performance WITH THE WINOSONG THE WHOLE IS TRULY GREATER THAN THE SUM OF ITS PARTS Windsong 19995Camano 15995Pixy 14995 Send 2 stamps catalog VHS video tape too can made readily-avail able materials youll have build some sophisticated electronics make work Please forward questions SASE author Happy Electric Landings Bob Kopski 25 West End Dr Lansdale PA 19446 RC Giant Scale/Beckman Continued page 53 dont miss information con tact Lee Taylor 216 Willow Ave Rose ville CA 95678 phone number 916 783-4190 next have information all-time favorite events STARS Scale Rally Olean NY scheduled July 6 7 year another event limited Giant Scale dont see much else flying site hospitality fantastic place might see Giant Scale aircraft IMAA Fun-Fly Festival IMAA bash year set July 18-21 Mobile AL fifth year event note time change August July Like Nats FFF rotating around different loca tions year like idea since gives IMAA members around country chance participate what Im hearing will another great Im putting weight just reading menus picnic ban quet Yes Mortimer Giant Scalers other things besides fly big birds things eat info available Don Godfrey 91 Blackstone Ave Binghamton NY 13903 telephone 607 724-0115 Bob Beckman 8248 Holly Grove Ct Manassas VA 22110 RC Pylon Racing/Hager Continued page 54 does make wheel pants last longer Well doesnt shock actually destroys wheel pants eliminated attaching land ing gear General Electrics clear bath tub caulking compound assure get proper shock mount slide wheel pant up landing gear place caulking compound backside landing gear pant gear meet Slide back down line up hole gear pant clean unwant ed caulk away Caution Clean out screw hole could lock up wheels install Now assuming final attach ment ie wheel pants painted use Loc-Tite product secure wheels tighten down Allen wrench four-way wrench Place piece vinyl tape over hole unit complete experience using method has nothing convenience factor No special wrench tighten nut easy replacement easy paint touch-up lower-portion damage easy in-field repair replacement longer life wheel pants Hopefully experience will same See next mouth Bill Hager 706 Glen Haven Dr Conroe TX 77385 RC Helicopters/Jolly Continued page 55 really impressed some particular Airtronics 94554 heavyduty servo has proved excellent choice use Helicopter servo features coreless motor ball-bearingsupported output shaft good centering great strength Ive found servo particular value using flybarless rotor system Because heavy feed back loads some servos fail short time have putting lot hours set 94554s prototype GMP flybarless system over last nine months am very satisfied After reading above might think 94554 good flybarless machine quite contrary little thing works well under strenuous en vironment theyre better Bell Hiller system Another product found very useful American RCs new Lok N-Start starting system really dont like starting belts have admit starting cones work fine until starter slips off cone either goes through cabin adds burnished look finish Scale ship So what Lok-N-Start Basically unit consists two parts adapter shaft telescopes over starting shaft machine held place setscrews starter-adap ter another shaft screws onto end starter has Torrington clutch other end Starting accom plished inserting starter over adapter squeezing switch Because Torrington one-way clutch starter cannot keep engine ac celerating once have gotten fire Best off no friction necessary except transferred Torrington very clean simple system should have thought years ago works great months photos addition photo Jack Schultzs coaxial scratchbuilt have scratch-built-fuselage 152 ModelAviation
Edition: Model Aviation - 1985/05
Page Numbers: 50, 51, 148, 149, 150, 151, 152
Radio Control Electrics Bob Kopski CHARGE months column going address most-often-askedabout topics charging particular gonna see make charging system will handle popular motor battery packs system present ed very simple reliable inex pensive can built nearly anybody requires no soldering special tools instruments material can purchased Radio Shack hobby shop hardware auto parts stores Its based something probably already have Astro Leisure similar charger addition well use to see some past lessons Basic Electricity can applied real work ing Electric hardware Lets get charger system pictured consists four main items conventional charger Electric cars planes Voltage Inverter Radio Shack catalog no 22-129 simple resistor bank resistors also Radio Shack some assort ed small items such lamp cord clips ordinary household switch wall box assorted wood pieces some nutz boltz purpose system permit easy charging motor battery pack youre likely find up 14 cells system no longer necessary split up two six-cell seven-cell packs otherwise connected series model make 12-cell 14-cell packs get completely frustrated trying charge ordinary single seven-cell packs grieve no longer answer simple circuit device shown figure unit powered via fairly heavy input cables car battery must connected directly battery posts input 12 volts powers Voltage Inverter turn doubles 12 volts 24 volts capable delivering up three amps output current elevated voltage level very efficient reliable manner have run couple Inverters hours overstressed condition no problems no overheating standard three-way household light switch really single-pole doublethrow switch selects either incoming 12 volt positive line 24 volt positive Voltage Inverter output allocates selection via homemade resistor net works cut voltage steps regular charger Just choose voltage job hand will discussed later resistor bank pictured really pair two distinct resistor sets resistors chosen readily avail able types capable handling just slightly over three amps Thus rated consistent Voltage verter ratings schematic shows resistor bank consists six oneohm 10-watt resistors connected series string series resistors forms 'coarse' currentadjustment device powered switch output arm simpler resistor bank special grouping few resistors powered negative auto battery power input lead serves fine adjustment device resistors mechanically elec trically assembled simple posts consist ing ordinary No 6 No 8 No 10 machine screw hardware normal use resistors will get hot ab solutely necessary assemble resistor banks manner like shown photo will melt solder solder assembled please save yourself trouble way An aluminum foil reflector double-sticky-taped %-in birch plywood resistor plate prevents burning wooden mount 50 Model Aviation Bobs highly-versatile heavy-duty charging system its easily made read column readily-available partseverything mounts 9 13-in 1/4-ln ply base Pro tective cage aluminum window screen material Note cage rails wooden located over resistorsbut over resistor leads Thats because resistors get HOT during charge tube merely holds various chaer cords Photo below gives better idea lead lengthsinput leads doubled lengths No 16 lamp cord wire color-coded light positive dark negative must connected proper terminals car battery Ni-Cd flight pack being recharged drawl ng gives circuit design 1 L SPECIAL NOTE VOLTAGE INVERTER RUNS CONSTANTLY DRAWS VERY LITTLE WHEN 24V POSITION IS NOT IN USE INVERTER IN-LINE FUSE HOLDER RADIO SHACK VOLTAGE BLACK#22129 RED 24V GREEN oJ 12V 3-WAY HOUSEHOLD WALL SWITCH TOP VIEW WIRE N UT 12 0R4-24V SWITCH SELCTED SIXtlA lOW RESISTORS RADIO SHACK #271-131 OHMS 0 2 3 4 5 6 0 1/4 RED 0 OLK 0~~~1 vW 3/4 TOP VIEW RESISTOR ASSEMBLY DOTTED WIRING BOTTOM SIDE FOUR O47n SW LARGE AUTORESISTORS ERY CLIPSRADIO SHACK *271130 TO MOTOR BATTERYCHARGER simple cover screen made ordi nary household aluminum door screen epoxied wooden rails prevents acciden tal contact hot resistors two resistor banks have multiple-output taps various individual resistor intersections screw posts become input connections charger clip leads connected red positive charger clip lead connect ed seven coarse positive resistor screw posts black negative charger clip lead goes remaining four fine negative screw 'posts' conventional charger output con nector plugs model battery pack other aspects its operation remain normal except some small points made later Thus charg er timer switch used before charger current meter used before fact familiar meter strument youll need know thing working OK Now some words about works past two columns Basic Electricity installments know current circuit determined available voltage divided cir cuit resistance also know voltage charging sourcethe auto batteryis ordinarily 12 volts fact can does vary somewhat over somewhat under 12 volts 24 volt Inverter output will follow input variation Also know model power-system battery being Ni-Cd dis plays fairly predictable terminal voltage too has some variation around nominal point basic importance understand what meant available circuit voltage schematic consistent familiar practice obvious model battery can charged source voltage greater two Thus familiar example six-cell NiContinued page 148 Twin resistor bank 1 mounts 5 x 7 piece hIn birch piy Note aluminum foil heatrefiector Four resistors ieft 047 ohm posts 27k-in centers Larger resistors ohm mounted 3-in centers DO NOT SOLDER THE LEADS TO THE POSTSthe joints might meit servicel Wiring backside resistor bank iooks ilke Center Use No 16 No 18 Wirestranded soi id soiid easier handie Note wiring smaii resistors bottom wires simple series Detali shot R resistor bank shows use brightpiated 632 machine screws nuts washers lock washers Screws 1 1A long spaced /z span aiiow resistor bodies bunch upthey must remain separated proper cooling May1985 51 WIRE NUT 5-6 16 GAUGE LAMP CORD PAIRS inside switch boxwire nuts used connect everything Switch screws near side connected red output iead Voltage inverter L other R goes positive resistor set hidden back switch ties car batterys posi tive input cabie black fused lead Voltage Inverter Note strain relief cable clamp discussed quite few club newsletters subject noise mufflers Most about necessity improve noise situation using better mufflers Almost club Ive involved last 15 years least formal muffler rule Some quite specific Nowadays almost everyone uses mufflers engines However middle Sixties almost nobody used Engines loud muffler propo nents claimed use mufflers would guarantee against loss fly ing field due noise problems early mufflers did lot quiet engines expense losing lot power Modern mufflers good job reduc ing noise sacrificing power remember thinking time club Western Ohio Radio Kontrol Socie ty required use mufflers about 1967 question time before everyone would forget what like before started using mufflers noise complaints would start again As know situation upon us As much hate think unless dra matic new improvements made mufflers two-cycle engines lot flying fields will lost other alternative can see clubs noise problems ban two-cycle engines favor four-cycle engines thats done wonder long will take flying field neighbors forget before four-cycle engines required start complaining again second item Id like share club newsletters pub lished Mount Rainier Radio Con trol Society Newsletter Tacoma WA Its semi-anonymous author Bill D wrote Old Threat Finally Identified Field Psychologist Glitchus Crashemup commonly known glitch has finally identified after years research dread malady preys upon certain segment species Homo Sapiens known RC Pilots normally lurking open fields grown men play model air craft glitch very dangerous full plumage adult male should approached experienced glitch hunters wielding loaded field strength meters has bite produces im mediate reactions beginning ner vous shaking twitching thumbs sequence symptoms often followed cries dont have Splintering thudding noises occur almost immediately point vic tim usually lapses depression may become militant approached next few minutes glitch invisible real imagined experience enemy should reported immediate ly field psychologist Ron Van Putte 111 Sleepy Oaks Rd Ft Walton Beach FL 32548 RC Electrics/Kopski Continued page 51 Cd will under charge eventually reach voltage its terminals equal about 15 x 6 about nine volts since Ni-Cds float up 15 volts per cell under charge take source volt age auto battery 12 volts avail able circuit voltage simply three volts difference 12 nine volts voltage appears across charging circuit resistance ear lier lessons circuit current charg ing current established choosing suitable resistor charge system design has plenty resistors choose Lets figure out make choice Last month saw several ways write Ohms Law Youll remember law relates three common elec trical terms voltage V current resistance R particular saw resistance can found dividing available circuit voltage ACV cir cuit current like R As example lets say six-cell pack made up 800 MAh cells Three amps very good charge current use 148 Model Aviation -I A monthly publication covering International RC Soaring Scene $1 6/yr US Canada & Mexico $24/yr elsewhere via airmail Post Office Box 269 Peterborough NH 03458 convenient Thus R lts divided 3 amps 1 ohm Clearly have connect charger clip leads resistor posts total resistance tapped off ohm could simply put black lead negative 0 ohms post red lead positive 1 ohm tap thats just sure everything OK simply note charger ammeter reading dial up timer switch should now clear what have really same old charger used using now choice supply voltages very convenient set selectable resistors fact no need go through arithmetic shown above practice just select desired source voltage switch connect charger input leads two resistor sets point highest resistance lowest current connect model battery start timer switch check ammeter reading Move clip leads lower values resistance increase charge current value desired over three amps An effective procedure arriving needed resistance start both high resistance taps move through coarse set steps ohm until youre close tobut low sideof desired current move through fine steps fine tune desired value can motor bat tery up 14 cells further note practical nature charging current will gradually decrease during time required charge because terminal voltage model pack will slowly rise available circuit voltage voltage across chosen resistor will decrease could just keep changing taps its necessary After two uses will become clear much current drop will can simply start little above desired value because know cur rent will slowly drop below its average current thats important provid ed variation too great similar vein car battery will gradually lower its voltage during busy day flying taps used earlier day will ones chosen later beauty design should always able ad just good charge Now lets examine special frustrating case seven-cell system read ers have told trouble exper ience getting good charge such motor pack Following six-cell example above can see sevencell pack will climb total voltage Signal Guard blocks random noise oft-frequency signals can cause loss control air land RC models Signal Guard responds sig nals its own precisely tuned fre quency ignoring static noise craft itself Plus additional amplification allows control operators visual limit Special Introductory Offer 87w about 15 x 7 105 voltsor moreas charge progresses 12 volt auto battery available circuit voltage 12 15 volts Obviously small voltage requires very small circuit resistance attain reasonable charg ing current Its under conditions things like good battery-clip contact good charger connection model power system extremely importantand also often unreliable beginning charge battery voltage relatively low say about 12 x 7 84 volts available circuit voltage 12 6 volts Thus beginning charge later ACV varies over 21and would charge want spend time flying less time money repairing crashed model Signal Guard answer Call toll-free 1-800-468-8215 order Signal Guard TM major credit card send $150 check money order Thlls PO Box 30179 Portland OR 97230 Oregon call collect 503-257-0912 current given circuit resistance Thus typical seven-cell pack 12 volt supply can have both unreliable circuit resistance highly variable ACV together can result very questionable charge course charge system shown least allows easy adjustment current-controlling taps theres better approach problem system presented can very good job charging seven-cell packs switching 24 volt position tap ping off enough resistance establish desired current two example bat tery voltages mentioned above ACV would 24 135 24 156 volts respectively May1985 149 90 day warranty. Selected dealerships available variation case clearly very small thus charge current will much constant Also selected resis tance will over four ohmsmuch would used above much stable forgiving contact resis tance variation Thus excellent charge available seven-cell packs should clear discussions above can generalized number cells fact smaller number cells model battery controlled charge con versely smaller ACV un reliable charge As rule thumb suggest using 12 volt position six fewer cells 24 volt option seven cells Naturally charging 14 cells will worst case regard possible use 24 volts time can fact almost left out 12/24 switch just used 24 volt Voltage Inverter output However considera tion highlights two known disadvantages charge system may relatively inefficient depending its used charging techniques use~ power auto battery needed charge model battery wasted power appearsyou guessed itas heat waste larger greater ACV Therefore some may consider prudent use lower two available source voltages possi ble Also lower-voltage position necessary have very small packs such small-capacity two three fourcell configurations As side point interest power wasted heat other charg er really no big deal should annoyance Consider common household 60 watt light bulb Surely no would wrap hand around thats few minutesits hot purpose light bulb provide light heat Only very small amount con sumed electrical power ever makes its way form light energyits virtual ly wasted heat Thus com mon light bulb very inefficient device second disadvantage charge system previously-mentioned threeamp limit Remember limit imposed Voltage Inverter specifica tion choice resistors Lets apply some Basic Electricity illus trate latter point resistors used Radio Shack 10 watt components description much power can safely dissi pate heat Last month learned power resistor such flashlight lamp discussed equal x x R case know resis tance Lets pick ohm resistor know power ratingits 10 watts two pieces information can find maximum current allowed thus P R Pxl0 atts rewriting 12 = 10 1 i/i3l6 amps example can see use fulness having some knowledge basic electricity back disadvantage itself As mentioned earlier three amps very convenient current charging 800 mali cells what use Thats because charger timer switches 15-minute clocks 3 amps x 15 minutes 45 ampminutes 4500% mAh just little short label capacity cells question represents safe charge put nearly-dead pack what about 12 Ah cells Well takes three amps about 12/3 x 60 24 minutes reach label capacity would charge about 20 minutes perfectly safe carefree charge dead Thus disadvantage have charge 12 Ah packs 15 minutes dial five timer other hand much better getting questionable charge some other less-controlled way have down path will SAILPLANES WORLD iSOlA Coffee Rd Modesto CA 95355 Sailplanes International Krause MultiPlex Wanitschek Wik & Roke Sport-Scale-F3B European Hardware Accessories Send $500 Cat & Price List 209 577-0506 IntducIng. Ereb cr11 RIC Idle-Bar Glow Plugs Long Short Also.Only $169 Traditional line non-idle bar Glow Plugs Six Types 3 Heat Ranges High Performance Glow Element Blow Proof Seal Only I Swanson Associates_ PO Box 151 e NJ 07470 5/Mi ______ 150 Model Aviation ELECTRIC MODEL & SAILPLANE SPECIALISTS 1981 World Soaring Champ DWIGHT HOLLEY IS PROUD TO ANNOUNCE NEW COMPANY TO HELP BOTH BEGINNER & EXPERT FLY INTO THE NEW ERA OF ELECTRIC AIRCRAFT WE ALSO OFFER SELECT FEW PURE SAILPLANES FREE DEMONSTRATION FLIGHTS CHECK OUT UNGlUE TEST FLIGHTS OF YOUR NEW PLANES CALL OR WRITE FOR FREE DESCRIPTIVE FLYER UPS C 00 FOR IMMEDIATE SHIPMENT ELECTRIC KITS IN STOCK AEROBATIC OLOTIMER SPORT SCALE GLIDERS HOLLEYS SILENT FLIGHT 203 748-0083 151 CHESTNUT RIDGE ROAD BETHEL CT 06801 FEATURING ONLY STATE OF THE ART ITEMS 01 51 01 01 n 0 z -I 0 r r 01 01 5 a z vi r m 5 know what mean Now lets talk about what chargers YOU can use system As far know Astros Leisures products capable handling 24 volt input such two 12 volt batteries series will work think Leisure digital chargera very popular productmay used above some limited voltage should check Roland Boucher before try applies whether youre using approach other higher source voltage Also Astros 4005D very popular charger because its built-in adjust ability However please note charger capable handling high input voltage charge just few cells defectits simply intended dissipate several watts its versatile solid state adjust ment circuitry suggest set con trol full click switch rotary control use system will work just fine Also chargers such pictured article 4005D have trickle charge circuit allows small current flow model battery after high-rate charge terminated time switch Astro uses small lamp Leisure small resistor across internal timer contacts components may able tolerate 24 volt input real ly needed purposes anyway Per sonally would simply disconnect such internal parts usually just wired timer screw terminals theres matter some charg ers having large fixed internal resistors particular charging job Leisure charger pictured herein way has switch-selectable resistor use popular RC cars having six seven-cell 12 aH packs resistors simply become resistance complete circuit charging system ordi narily should pose no problem application cannot tolerate add ed resistance simply short resistors out wire jumper Finally charger shown held system baseboard doublesticky-backed Velcro Radio Shack As such easily lifted assembly use usual input output wires have left intact rfo internal modifications have made its perfectly normal device removed environment charge system simple system quite work able very wide range applications theres can done fact Ill presenting deluxe charge system later will based two modified Voltage Inverters supplemented highly-efficient smoothly-adjustable solid state switching mode electronic current-regulator will charge batteries up 30 volts beyond four amps SAILPLANE LAUNCH EQUIPMENT FOR EVERY FIELD $23495 source QUIET FLIGHT Supplies hi-starts electric motors& reducers bat te r aes pa rachu tes tow line drums accessories braided nylon Iinethe PRO PHEY PROPHET 941CURTISS ROBINaL CRATE kits VISA MASTERCARD h EDAVEY EUSYSTEMS m VU CORPORATION ONE WOOD LANEMALVERNPA 19355 215644-6772 Write call information May1985 151 iro Box 10630 Lorain Ohio 44055 APhone 216282-8354 Peanut Scale Models Piper Vigabond Piper Cub 0linsgn 125 utdeor kits nh. $650 Light Indoor kits.. $695 Sport Scale Models 22 Span PC-6 Porter Taylor Craft Stinsan Voyager Rubber CO2 Power PC-B POft&Kits each. $750 Soort Models An Embryo Model 18 Span designed wiol beginners Experts HARD-TO-FIND ITEMS FOR YOUR BUILDING NEEDS Early Bird Tissue br Antique Aircratt S595 True Olde Japanese Tissue 10 3 colors 95 Japanese Tissue 12 6 colors $395 Microlite Plain$325 Silver$395 Microfilm Glue Solvent Condenser Paper 3 sheets 5375 Plan Service over 17 Scale Sport Scale & Peanut Scale Rubber Strip 020 thro 085each 5175 3/32 tliru 5/32each 5195 Winder 61 395 Mark 1161 195 Complete Line 01 Brown CO2 Motors Balsa Wood Outdoor & Indoor Sheets & Strips Add 10% Poutage mum Postage $150 COMPLETE CATALOG 5150 C battery yet Secinied POWRZOOM$36995 RETRBEVER$26495 El S 4 hi 01 01 z 01 a a 201 SE 12thStreeo Pompano Beach FL 33060 305-785-7978 INC TIlE LANOIIIG GEAf eEoPtE Tired kil landing goaro 181 dont III ynar biggie properly o & II Eagineering can salvo yaor problems * CesIum boilt yoor eteds & specs guaranteed III * Strong & durable wiIbslad Ike laugheet aiding * It & Engineering gear will wark & keep yoor biggie flying * Ia clock roplacoineat gear popular models Byron PIlls Christ Eagle CAP 21 gals0 ISA J-3 CUB Air Tack Pawnee Eagle Nosen Big Slick Cbamp Citabria g & g madels Snapper Stinger Seapper Tue 4 THE COMPETITIONS VIEW 'I OF THE WINDSONG I. C, 0 0 N 0 DODGSON DESIGNS 2904 SW CAMANO DRIVE CAMANO ISLAND WA 9825i2J What makes Windsong best plane have deadair lightlift gusting 25 MPH winds thermal contest What makes windsong best plane have x-country race Some say 11to 1 aspect ratio clean solidcore wing no spoiler bays disturb airflow Others say Eppler 214 airfoil combined exclusive full-span camber changing capability including elevator compensated 80 degree flaps reflexible ailerons fact design innovations contribute Windsongs total design concept its unprecedented performance WITH THE WINOSONG THE WHOLE IS TRULY GREATER THAN THE SUM OF ITS PARTS Windsong 19995Camano 15995Pixy 14995 Send 2 stamps catalog VHS video tape too can made readily-avail able materials youll have build some sophisticated electronics make work Please forward questions SASE author Happy Electric Landings Bob Kopski 25 West End Dr Lansdale PA 19446 RC Giant Scale/Beckman Continued page 53 dont miss information con tact Lee Taylor 216 Willow Ave Rose ville CA 95678 phone number 916 783-4190 next have information all-time favorite events STARS Scale Rally Olean NY scheduled July 6 7 year another event limited Giant Scale dont see much else flying site hospitality fantastic place might see Giant Scale aircraft IMAA Fun-Fly Festival IMAA bash year set July 18-21 Mobile AL fifth year event note time change August July Like Nats FFF rotating around different loca tions year like idea since gives IMAA members around country chance participate what Im hearing will another great Im putting weight just reading menus picnic ban quet Yes Mortimer Giant Scalers other things besides fly big birds things eat info available Don Godfrey 91 Blackstone Ave Binghamton NY 13903 telephone 607 724-0115 Bob Beckman 8248 Holly Grove Ct Manassas VA 22110 RC Pylon Racing/Hager Continued page 54 does make wheel pants last longer Well doesnt shock actually destroys wheel pants eliminated attaching land ing gear General Electrics clear bath tub caulking compound assure get proper shock mount slide wheel pant up landing gear place caulking compound backside landing gear pant gear meet Slide back down line up hole gear pant clean unwant ed caulk away Caution Clean out screw hole could lock up wheels install Now assuming final attach ment ie wheel pants painted use Loc-Tite product secure wheels tighten down Allen wrench four-way wrench Place piece vinyl tape over hole unit complete experience using method has nothing convenience factor No special wrench tighten nut easy replacement easy paint touch-up lower-portion damage easy in-field repair replacement longer life wheel pants Hopefully experience will same See next mouth Bill Hager 706 Glen Haven Dr Conroe TX 77385 RC Helicopters/Jolly Continued page 55 really impressed some particular Airtronics 94554 heavyduty servo has proved excellent choice use Helicopter servo features coreless motor ball-bearingsupported output shaft good centering great strength Ive found servo particular value using flybarless rotor system Because heavy feed back loads some servos fail short time have putting lot hours set 94554s prototype GMP flybarless system over last nine months am very satisfied After reading above might think 94554 good flybarless machine quite contrary little thing works well under strenuous en vironment theyre better Bell Hiller system Another product found very useful American RCs new Lok N-Start starting system really dont like starting belts have admit starting cones work fine until starter slips off cone either goes through cabin adds burnished look finish Scale ship So what Lok-N-Start Basically unit consists two parts adapter shaft telescopes over starting shaft machine held place setscrews starter-adap ter another shaft screws onto end starter has Torrington clutch other end Starting accom plished inserting starter over adapter squeezing switch Because Torrington one-way clutch starter cannot keep engine ac celerating once have gotten fire Best off no friction necessary except transferred Torrington very clean simple system should have thought years ago works great months photos addition photo Jack Schultzs coaxial scratchbuilt have scratch-built-fuselage 152 ModelAviation
Edition: Model Aviation - 1985/05
Page Numbers: 50, 51, 148, 149, 150, 151, 152
Radio Control Electrics Bob Kopski CHARGE months column going address most-often-askedabout topics charging particular gonna see make charging system will handle popular motor battery packs system present ed very simple reliable inex pensive can built nearly anybody requires no soldering special tools instruments material can purchased Radio Shack hobby shop hardware auto parts stores Its based something probably already have Astro Leisure similar charger addition well use to see some past lessons Basic Electricity can applied real work ing Electric hardware Lets get charger system pictured consists four main items conventional charger Electric cars planes Voltage Inverter Radio Shack catalog no 22-129 simple resistor bank resistors also Radio Shack some assort ed small items such lamp cord clips ordinary household switch wall box assorted wood pieces some nutz boltz purpose system permit easy charging motor battery pack youre likely find up 14 cells system no longer necessary split up two six-cell seven-cell packs otherwise connected series model make 12-cell 14-cell packs get completely frustrated trying charge ordinary single seven-cell packs grieve no longer answer simple circuit device shown figure unit powered via fairly heavy input cables car battery must connected directly battery posts input 12 volts powers Voltage Inverter turn doubles 12 volts 24 volts capable delivering up three amps output current elevated voltage level very efficient reliable manner have run couple Inverters hours overstressed condition no problems no overheating standard three-way household light switch really single-pole doublethrow switch selects either incoming 12 volt positive line 24 volt positive Voltage Inverter output allocates selection via homemade resistor net works cut voltage steps regular charger Just choose voltage job hand will discussed later resistor bank pictured really pair two distinct resistor sets resistors chosen readily avail able types capable handling just slightly over three amps Thus rated consistent Voltage verter ratings schematic shows resistor bank consists six oneohm 10-watt resistors connected series string series resistors forms 'coarse' currentadjustment device powered switch output arm simpler resistor bank special grouping few resistors powered negative auto battery power input lead serves fine adjustment device resistors mechanically elec trically assembled simple posts consist ing ordinary No 6 No 8 No 10 machine screw hardware normal use resistors will get hot ab solutely necessary assemble resistor banks manner like shown photo will melt solder solder assembled please save yourself trouble way An aluminum foil reflector double-sticky-taped %-in birch plywood resistor plate prevents burning wooden mount 50 Model Aviation Bobs highly-versatile heavy-duty charging system its easily made read column readily-available partseverything mounts 9 13-in 1/4-ln ply base Pro tective cage aluminum window screen material Note cage rails wooden located over resistorsbut over resistor leads Thats because resistors get HOT during charge tube merely holds various chaer cords Photo below gives better idea lead lengthsinput leads doubled lengths No 16 lamp cord wire color-coded light positive dark negative must connected proper terminals car battery Ni-Cd flight pack being recharged drawl ng gives circuit design 1 L SPECIAL NOTE VOLTAGE INVERTER RUNS CONSTANTLY DRAWS VERY LITTLE WHEN 24V POSITION IS NOT IN USE INVERTER IN-LINE FUSE HOLDER RADIO SHACK VOLTAGE BLACK#22129 RED 24V GREEN oJ 12V 3-WAY HOUSEHOLD WALL SWITCH TOP VIEW WIRE N UT 12 0R4-24V SWITCH SELCTED SIXtlA lOW RESISTORS RADIO SHACK #271-131 OHMS 0 2 3 4 5 6 0 1/4 RED 0 OLK 0~~~1 vW 3/4 TOP VIEW RESISTOR ASSEMBLY DOTTED WIRING BOTTOM SIDE FOUR O47n SW LARGE AUTORESISTORS ERY CLIPSRADIO SHACK *271130 TO MOTOR BATTERYCHARGER simple cover screen made ordi nary household aluminum door screen epoxied wooden rails prevents acciden tal contact hot resistors two resistor banks have multiple-output taps various individual resistor intersections screw posts become input connections charger clip leads connected red positive charger clip lead connect ed seven coarse positive resistor screw posts black negative charger clip lead goes remaining four fine negative screw 'posts' conventional charger output con nector plugs model battery pack other aspects its operation remain normal except some small points made later Thus charg er timer switch used before charger current meter used before fact familiar meter strument youll need know thing working OK Now some words about works past two columns Basic Electricity installments know current circuit determined available voltage divided cir cuit resistance also know voltage charging sourcethe auto batteryis ordinarily 12 volts fact can does vary somewhat over somewhat under 12 volts 24 volt Inverter output will follow input variation Also know model power-system battery being Ni-Cd dis plays fairly predictable terminal voltage too has some variation around nominal point basic importance understand what meant available circuit voltage schematic consistent familiar practice obvious model battery can charged source voltage greater two Thus familiar example six-cell NiContinued page 148 Twin resistor bank 1 mounts 5 x 7 piece hIn birch piy Note aluminum foil heatrefiector Four resistors ieft 047 ohm posts 27k-in centers Larger resistors ohm mounted 3-in centers DO NOT SOLDER THE LEADS TO THE POSTSthe joints might meit servicel Wiring backside resistor bank iooks ilke Center Use No 16 No 18 Wirestranded soi id soiid easier handie Note wiring smaii resistors bottom wires simple series Detali shot R resistor bank shows use brightpiated 632 machine screws nuts washers lock washers Screws 1 1A long spaced /z span aiiow resistor bodies bunch upthey must remain separated proper cooling May1985 51 WIRE NUT 5-6 16 GAUGE LAMP CORD PAIRS inside switch boxwire nuts used connect everything Switch screws near side connected red output iead Voltage inverter L other R goes positive resistor set hidden back switch ties car batterys posi tive input cabie black fused lead Voltage Inverter Note strain relief cable clamp discussed quite few club newsletters subject noise mufflers Most about necessity improve noise situation using better mufflers Almost club Ive involved last 15 years least formal muffler rule Some quite specific Nowadays almost everyone uses mufflers engines However middle Sixties almost nobody used Engines loud muffler propo nents claimed use mufflers would guarantee against loss fly ing field due noise problems early mufflers did lot quiet engines expense losing lot power Modern mufflers good job reduc ing noise sacrificing power remember thinking time club Western Ohio Radio Kontrol Socie ty required use mufflers about 1967 question time before everyone would forget what like before started using mufflers noise complaints would start again As know situation upon us As much hate think unless dra matic new improvements made mufflers two-cycle engines lot flying fields will lost other alternative can see clubs noise problems ban two-cycle engines favor four-cycle engines thats done wonder long will take flying field neighbors forget before four-cycle engines required start complaining again second item Id like share club newsletters pub lished Mount Rainier Radio Con trol Society Newsletter Tacoma WA Its semi-anonymous author Bill D wrote Old Threat Finally Identified Field Psychologist Glitchus Crashemup commonly known glitch has finally identified after years research dread malady preys upon certain segment species Homo Sapiens known RC Pilots normally lurking open fields grown men play model air craft glitch very dangerous full plumage adult male should approached experienced glitch hunters wielding loaded field strength meters has bite produces im mediate reactions beginning ner vous shaking twitching thumbs sequence symptoms often followed cries dont have Splintering thudding noises occur almost immediately point vic tim usually lapses depression may become militant approached next few minutes glitch invisible real imagined experience enemy should reported immediate ly field psychologist Ron Van Putte 111 Sleepy Oaks Rd Ft Walton Beach FL 32548 RC Electrics/Kopski Continued page 51 Cd will under charge eventually reach voltage its terminals equal about 15 x 6 about nine volts since Ni-Cds float up 15 volts per cell under charge take source volt age auto battery 12 volts avail able circuit voltage simply three volts difference 12 nine volts voltage appears across charging circuit resistance ear lier lessons circuit current charg ing current established choosing suitable resistor charge system design has plenty resistors choose Lets figure out make choice Last month saw several ways write Ohms Law Youll remember law relates three common elec trical terms voltage V current resistance R particular saw resistance can found dividing available circuit voltage ACV cir cuit current like R As example lets say six-cell pack made up 800 MAh cells Three amps very good charge current use 148 Model Aviation -I A monthly publication covering International RC Soaring Scene $1 6/yr US Canada & Mexico $24/yr elsewhere via airmail Post Office Box 269 Peterborough NH 03458 convenient Thus R lts divided 3 amps 1 ohm Clearly have connect charger clip leads resistor posts total resistance tapped off ohm could simply put black lead negative 0 ohms post red lead positive 1 ohm tap thats just sure everything OK simply note charger ammeter reading dial up timer switch should now clear what have really same old charger used using now choice supply voltages very convenient set selectable resistors fact no need go through arithmetic shown above practice just select desired source voltage switch connect charger input leads two resistor sets point highest resistance lowest current connect model battery start timer switch check ammeter reading Move clip leads lower values resistance increase charge current value desired over three amps An effective procedure arriving needed resistance start both high resistance taps move through coarse set steps ohm until youre close tobut low sideof desired current move through fine steps fine tune desired value can motor bat tery up 14 cells further note practical nature charging current will gradually decrease during time required charge because terminal voltage model pack will slowly rise available circuit voltage voltage across chosen resistor will decrease could just keep changing taps its necessary After two uses will become clear much current drop will can simply start little above desired value because know cur rent will slowly drop below its average current thats important provid ed variation too great similar vein car battery will gradually lower its voltage during busy day flying taps used earlier day will ones chosen later beauty design should always able ad just good charge Now lets examine special frustrating case seven-cell system read ers have told trouble exper ience getting good charge such motor pack Following six-cell example above can see sevencell pack will climb total voltage Signal Guard blocks random noise oft-frequency signals can cause loss control air land RC models Signal Guard responds sig nals its own precisely tuned fre quency ignoring static noise craft itself Plus additional amplification allows control operators visual limit Special Introductory Offer 87w about 15 x 7 105 voltsor moreas charge progresses 12 volt auto battery available circuit voltage 12 15 volts Obviously small voltage requires very small circuit resistance attain reasonable charg ing current Its under conditions things like good battery-clip contact good charger connection model power system extremely importantand also often unreliable beginning charge battery voltage relatively low say about 12 x 7 84 volts available circuit voltage 12 6 volts Thus beginning charge later ACV varies over 21and would charge want spend time flying less time money repairing crashed model Signal Guard answer Call toll-free 1-800-468-8215 order Signal Guard TM major credit card send $150 check money order Thlls PO Box 30179 Portland OR 97230 Oregon call collect 503-257-0912 current given circuit resistance Thus typical seven-cell pack 12 volt supply can have both unreliable circuit resistance highly variable ACV together can result very questionable charge course charge system shown least allows easy adjustment current-controlling taps theres better approach problem system presented can very good job charging seven-cell packs switching 24 volt position tap ping off enough resistance establish desired current two example bat tery voltages mentioned above ACV would 24 135 24 156 volts respectively May1985 149 90 day warranty. Selected dealerships available variation case clearly very small thus charge current will much constant Also selected resis tance will over four ohmsmuch would used above much stable forgiving contact resis tance variation Thus excellent charge available seven-cell packs should clear discussions above can generalized number cells fact smaller number cells model battery controlled charge con versely smaller ACV un reliable charge As rule thumb suggest using 12 volt position six fewer cells 24 volt option seven cells Naturally charging 14 cells will worst case regard possible use 24 volts time can fact almost left out 12/24 switch just used 24 volt Voltage Inverter output However considera tion highlights two known disadvantages charge system may relatively inefficient depending its used charging techniques use~ power auto battery needed charge model battery wasted power appearsyou guessed itas heat waste larger greater ACV Therefore some may consider prudent use lower two available source voltages possi ble Also lower-voltage position necessary have very small packs such small-capacity two three fourcell configurations As side point interest power wasted heat other charg er really no big deal should annoyance Consider common household 60 watt light bulb Surely no would wrap hand around thats few minutesits hot purpose light bulb provide light heat Only very small amount con sumed electrical power ever makes its way form light energyits virtual ly wasted heat Thus com mon light bulb very inefficient device second disadvantage charge system previously-mentioned threeamp limit Remember limit imposed Voltage Inverter specifica tion choice resistors Lets apply some Basic Electricity illus trate latter point resistors used Radio Shack 10 watt components description much power can safely dissi pate heat Last month learned power resistor such flashlight lamp discussed equal x x R case know resis tance Lets pick ohm resistor know power ratingits 10 watts two pieces information can find maximum current allowed thus P R Pxl0 atts rewriting 12 = 10 1 i/i3l6 amps example can see use fulness having some knowledge basic electricity back disadvantage itself As mentioned earlier three amps very convenient current charging 800 mali cells what use Thats because charger timer switches 15-minute clocks 3 amps x 15 minutes 45 ampminutes 4500% mAh just little short label capacity cells question represents safe charge put nearly-dead pack what about 12 Ah cells Well takes three amps about 12/3 x 60 24 minutes reach label capacity would charge about 20 minutes perfectly safe carefree charge dead Thus disadvantage have charge 12 Ah packs 15 minutes dial five timer other hand much better getting questionable charge some other less-controlled way have down path will SAILPLANES WORLD iSOlA Coffee Rd Modesto CA 95355 Sailplanes International Krause MultiPlex Wanitschek Wik & Roke Sport-Scale-F3B European Hardware Accessories Send $500 Cat & Price List 209 577-0506 IntducIng. Ereb cr11 RIC Idle-Bar Glow Plugs Long Short Also.Only $169 Traditional line non-idle bar Glow Plugs Six Types 3 Heat Ranges High Performance Glow Element Blow Proof Seal Only I Swanson Associates_ PO Box 151 e NJ 07470 5/Mi ______ 150 Model Aviation ELECTRIC MODEL & SAILPLANE SPECIALISTS 1981 World Soaring Champ DWIGHT HOLLEY IS PROUD TO ANNOUNCE NEW COMPANY TO HELP BOTH BEGINNER & EXPERT FLY INTO THE NEW ERA OF ELECTRIC AIRCRAFT WE ALSO OFFER SELECT FEW PURE SAILPLANES FREE DEMONSTRATION FLIGHTS CHECK OUT UNGlUE TEST FLIGHTS OF YOUR NEW PLANES CALL OR WRITE FOR FREE DESCRIPTIVE FLYER UPS C 00 FOR IMMEDIATE SHIPMENT ELECTRIC KITS IN STOCK AEROBATIC OLOTIMER SPORT SCALE GLIDERS HOLLEYS SILENT FLIGHT 203 748-0083 151 CHESTNUT RIDGE ROAD BETHEL CT 06801 FEATURING ONLY STATE OF THE ART ITEMS 01 51 01 01 n 0 z -I 0 r r 01 01 5 a z vi r m 5 know what mean Now lets talk about what chargers YOU can use system As far know Astros Leisures products capable handling 24 volt input such two 12 volt batteries series will work think Leisure digital chargera very popular productmay used above some limited voltage should check Roland Boucher before try applies whether youre using approach other higher source voltage Also Astros 4005D very popular charger because its built-in adjust ability However please note charger capable handling high input voltage charge just few cells defectits simply intended dissipate several watts its versatile solid state adjust ment circuitry suggest set con trol full click switch rotary control use system will work just fine Also chargers such pictured article 4005D have trickle charge circuit allows small current flow model battery after high-rate charge terminated time switch Astro uses small lamp Leisure small resistor across internal timer contacts components may able tolerate 24 volt input real ly needed purposes anyway Per sonally would simply disconnect such internal parts usually just wired timer screw terminals theres matter some charg ers having large fixed internal resistors particular charging job Leisure charger pictured herein way has switch-selectable resistor use popular RC cars having six seven-cell 12 aH packs resistors simply become resistance complete circuit charging system ordi narily should pose no problem application cannot tolerate add ed resistance simply short resistors out wire jumper Finally charger shown held system baseboard doublesticky-backed Velcro Radio Shack As such easily lifted assembly use usual input output wires have left intact rfo internal modifications have made its perfectly normal device removed environment charge system simple system quite work able very wide range applications theres can done fact Ill presenting deluxe charge system later will based two modified Voltage Inverters supplemented highly-efficient smoothly-adjustable solid state switching mode electronic current-regulator will charge batteries up 30 volts beyond four amps SAILPLANE LAUNCH EQUIPMENT FOR EVERY FIELD $23495 source QUIET FLIGHT Supplies hi-starts electric motors& reducers bat te r aes pa rachu tes tow line drums accessories braided nylon Iinethe PRO PHEY PROPHET 941CURTISS ROBINaL CRATE kits VISA MASTERCARD h EDAVEY EUSYSTEMS m VU CORPORATION ONE WOOD LANEMALVERNPA 19355 215644-6772 Write call information May1985 151 iro Box 10630 Lorain Ohio 44055 APhone 216282-8354 Peanut Scale Models Piper Vigabond Piper Cub 0linsgn 125 utdeor kits nh. $650 Light Indoor kits.. $695 Sport Scale Models 22 Span PC-6 Porter Taylor Craft Stinsan Voyager Rubber CO2 Power PC-B POft&Kits each. $750 Soort Models An Embryo Model 18 Span designed wiol beginners Experts HARD-TO-FIND ITEMS FOR YOUR BUILDING NEEDS Early Bird Tissue br Antique Aircratt S595 True Olde Japanese Tissue 10 3 colors 95 Japanese Tissue 12 6 colors $395 Microlite Plain$325 Silver$395 Microfilm Glue Solvent Condenser Paper 3 sheets 5375 Plan Service over 17 Scale Sport Scale & Peanut Scale Rubber Strip 020 thro 085each 5175 3/32 tliru 5/32each 5195 Winder 61 395 Mark 1161 195 Complete Line 01 Brown CO2 Motors Balsa Wood Outdoor & Indoor Sheets & Strips Add 10% Poutage mum Postage $150 COMPLETE CATALOG 5150 C battery yet Secinied POWRZOOM$36995 RETRBEVER$26495 El S 4 hi 01 01 z 01 a a 201 SE 12thStreeo Pompano Beach FL 33060 305-785-7978 INC TIlE LANOIIIG GEAf eEoPtE Tired kil landing goaro 181 dont III ynar biggie properly o & II Eagineering can salvo yaor problems * CesIum boilt yoor eteds & specs guaranteed III * Strong & durable wiIbslad Ike laugheet aiding * It & Engineering gear will wark & keep yoor biggie flying * Ia clock roplacoineat gear popular models Byron PIlls Christ Eagle CAP 21 gals0 ISA J-3 CUB Air Tack Pawnee Eagle Nosen Big Slick Cbamp Citabria g & g madels Snapper Stinger Seapper Tue 4 THE COMPETITIONS VIEW 'I OF THE WINDSONG I. C, 0 0 N 0 DODGSON DESIGNS 2904 SW CAMANO DRIVE CAMANO ISLAND WA 9825i2J What makes Windsong best plane have deadair lightlift gusting 25 MPH winds thermal contest What makes windsong best plane have x-country race Some say 11to 1 aspect ratio clean solidcore wing no spoiler bays disturb airflow Others say Eppler 214 airfoil combined exclusive full-span camber changing capability including elevator compensated 80 degree flaps reflexible ailerons fact design innovations contribute Windsongs total design concept its unprecedented performance WITH THE WINOSONG THE WHOLE IS TRULY GREATER THAN THE SUM OF ITS PARTS Windsong 19995Camano 15995Pixy 14995 Send 2 stamps catalog VHS video tape too can made readily-avail able materials youll have build some sophisticated electronics make work Please forward questions SASE author Happy Electric Landings Bob Kopski 25 West End Dr Lansdale PA 19446 RC Giant Scale/Beckman Continued page 53 dont miss information con tact Lee Taylor 216 Willow Ave Rose ville CA 95678 phone number 916 783-4190 next have information all-time favorite events STARS Scale Rally Olean NY scheduled July 6 7 year another event limited Giant Scale dont see much else flying site hospitality fantastic place might see Giant Scale aircraft IMAA Fun-Fly Festival IMAA bash year set July 18-21 Mobile AL fifth year event note time change August July Like Nats FFF rotating around different loca tions year like idea since gives IMAA members around country chance participate what Im hearing will another great Im putting weight just reading menus picnic ban quet Yes Mortimer Giant Scalers other things besides fly big birds things eat info available Don Godfrey 91 Blackstone Ave Binghamton NY 13903 telephone 607 724-0115 Bob Beckman 8248 Holly Grove Ct Manassas VA 22110 RC Pylon Racing/Hager Continued page 54 does make wheel pants last longer Well doesnt shock actually destroys wheel pants eliminated attaching land ing gear General Electrics clear bath tub caulking compound assure get proper shock mount slide wheel pant up landing gear place caulking compound backside landing gear pant gear meet Slide back down line up hole gear pant clean unwant ed caulk away Caution Clean out screw hole could lock up wheels install Now assuming final attach ment ie wheel pants painted use Loc-Tite product secure wheels tighten down Allen wrench four-way wrench Place piece vinyl tape over hole unit complete experience using method has nothing convenience factor No special wrench tighten nut easy replacement easy paint touch-up lower-portion damage easy in-field repair replacement longer life wheel pants Hopefully experience will same See next mouth Bill Hager 706 Glen Haven Dr Conroe TX 77385 RC Helicopters/Jolly Continued page 55 really impressed some particular Airtronics 94554 heavyduty servo has proved excellent choice use Helicopter servo features coreless motor ball-bearingsupported output shaft good centering great strength Ive found servo particular value using flybarless rotor system Because heavy feed back loads some servos fail short time have putting lot hours set 94554s prototype GMP flybarless system over last nine months am very satisfied After reading above might think 94554 good flybarless machine quite contrary little thing works well under strenuous en vironment theyre better Bell Hiller system Another product found very useful American RCs new Lok N-Start starting system really dont like starting belts have admit starting cones work fine until starter slips off cone either goes through cabin adds burnished look finish Scale ship So what Lok-N-Start Basically unit consists two parts adapter shaft telescopes over starting shaft machine held place setscrews starter-adap ter another shaft screws onto end starter has Torrington clutch other end Starting accom plished inserting starter over adapter squeezing switch Because Torrington one-way clutch starter cannot keep engine ac celerating once have gotten fire Best off no friction necessary except transferred Torrington very clean simple system should have thought years ago works great months photos addition photo Jack Schultzs coaxial scratchbuilt have scratch-built-fuselage 152 ModelAviation