Radio Control: Electrics

MEET ANNOUNCEMENTS important lot folks Ill open again First serious competitors Harbor Soaring Society Costa Mesa CA has nounced Second Biannual Sportsmen/Novice F3E FAI Contest held August 19-20 1989 contest open US-resident AMA membersexcept nor open anyone qualified US AMA FAI F3E team cash prizes fourth place beginning $1000 first info please con tact Felix Vivas 1800 16th St #H-3 10 Newport Beach CA 92663 telephone 1-714/645-3263 tell im Bob sent ya Second Annual Electrifest scheduled September 16-17 1989 sponsored Sb Fliers Cuesta Community College San Louis Obispo CA have no details offer can contact CD Cal Drake Box 1557 Morro Bay CA 93442 Finally very same dates September 16-17 1989but other side countrythe Keystone RC Club will hosting Tenth Annual KRC Electric Fly meet will again held Buc-Le Aerosportsmen Field Quakertown PA field will unof ficially open early arrivals Friday afternoon September 15 courtesy Buc-Le Club years format will include meet has become famous plus some special activi ties celebration 10th anniversary will dinner/social Saturday evening least two complete ready-to-fly Electrics will given away Planned fun events include Up/Last-Down Maxi-Flight Most Loops Most Rollsall cash prizes fourth place Kopskls latest inventions pushrods Above large nylon clevis look closely CyA glued slightly tapered end 3A-in-sq balsa pushrod lack faith can strengthen joint binding Using threaded hole clevis guide #50 drill makes hole 1/2-In deep pushrod end Screw brass threaded coupler davis end Sal der Zbend made %2 wire Other end pushrod Below notched Zbent length threaded rod bound CyA-glued place end goes control surface plus other judgings prizes throughout weekend information contact columns author meets CD Bob Kopski 25 West End Dr Lansdale PA 19446 An advisory some Amptique kits passed Keith Shaw seems batch got out factory some rather soft 3A6-insq balsa intended wing spars whole buncha wings folded same day out Keiths way Anyone whos following column few months knows Im very big Amptique no way negative reflec tion very fine plane Rather its cau tionsince some things go wrong sometimes take good look spar material kit make sure suitable Better yet doubt suggest substitute Y16-in-sq spruce main panel spars go flying worry-frec course same idea could equally apply model Make sure spar material suitable Nuff said except Thanks Keith Larger power systems sometimes just lotsa flying smaller ones can wind up surprising dead car battery Yup can happen know Lets check out some numbers Lets say have 40 18 1200 Ah cells nominal charge pack 15 minutes times 40-45 amps average cell voltage about 1 4 volts totals about 107 watt-hours However since probably charged modern booster-charger efficiency about 70%-80% really 143 watt-hour de Kopskis Astro cobalt 15 array props used generate data months column Prop top thin zero-pitch flat stick used determine motor k see last months column Inside view new Astro Model 112 AC/DC Constant Current Charger Theres stuff earlier Model 102 Kop ski has performance details month 42 Model Aviation Radio Conoi Electrics Bob Kopski 25 West End Dr Lansdale PA 19446 Jim Benners Lansing Ml Amp-Aqua-Tique Geared Astro 05 cobalt turns 11 x 6 nylon prop help seven 800mAh cells Jomar SC-S speed controller mand car battery nominal 12-volt lev el car battery delivering about 12 amps quarter-hour needed charge plane auto batteries new have nomi nal capacity around 50 ampere-hours less Some case 50 ampere-hour would ideally able charge model about 50 divided 12 divided 25 about 16 times reality auto batteries simply dont de liver rated capacity furthermore batter ies new Theres story get point should count average get about half little expected auto battery capacity have some margin left start car translates about eight-flight expectancy example course could less have other power demands place same time Perhaps some lights maybe youre fly ing big system along small Whatever possible get surprised days end car wont startso keep mind theres run down car battery depending type may also damage As best can tell popular maintenance-free batteries ones never need water furthermore sealed anyway prone significant degrada tion run down way deep cycled degradation takes form lost capacity means next time out fewer flights will run down seems continue until battery such deteriorated condi tion little value As best can determine what happened What really surprised Im ordi narily careful about much demand place car battery day ran down anyway Thereafter went downhill very rapidly described above car less year old turned out light cassette compartment time visible compartment door closed suspect battery well down because charging Exciter few times did Anyway wound up new battery elected install top-rated inciden tally limited maintenance type means water caps sealed can keep watch electrolyte level FurtherDent Hornswoggled lifelifles~ horn5 Th neW Theconsidere ur aircraft tanY ushrods very trO secotter InSyoU th rodsyOU re ohthe peratiofl tOJ cant enUSve HordurPUsk iocated WI control can trusttheiro ntro91kYo unf Ball Link ed tO0tating bcenter eccUfatethe0 Rotart thOUt neWi 0ffers ball link 0ye less what apPlicatl bh after WIhorn addition hornneed forneY0 PUnfroln expensi elim1 od WhY waste ~en can systems WY Roba effici save time moflorns Ball Link Contro VACUUM BAG LAY O$3995 GAPLESS ARROW SHAFT HINGE KITS Kit Includes bes a-Bushing & Screws 3 SIZES 013 Wall Thickness 7/320DX26$1195 9/32 OD X 30$1195 11/320DX33$1195 August 1989 43 Aero Zeta speed control Product Design Inc 16922 NE 124th St Redmond WA 98052 Firm makes several controls Elec trics unit has built-in electronic ther mal shutdown eliminates need sys tem fuse Arming switch also electronic functionnote its lightweight wiring rt MIg 1988PO Box 1247 St Charles Illinois 60174 VACUUM BAG SYSTEM FOR WING CONSTRUCTION SUCKERKl1rM$5995 PHONE 313 664-3330 Send $100 & SASE Product List Samples Real Wood Veneer Skins Dealer Inquiries Welcome avings up 40% asler enloyable protessiotal results ITO ORDER Send *1 coupon ____________________________________________ j ADDRESS ____________________________________________ Snyder Ave LBerkelev Heights NJ 07322CITY ___________________________STATE ______ ZIP _________ Continued page 134 Cirrus e51/fotk2 el-land-cut quality kit includes rigging scale control setup wire parts pre-bent custom brass hardware parts individually identified pack aged Complete decals Engine sizes 45-50 FS Wings fold next fuselage full scale removal four bolts Rigging intact setup time under 3 mm owing span 55 Stand off scale $15900 VlSAeMasterCardeMoney Order Michigan residents add 4% sales tax Add $550 P&H US orders $1500 Foreign Orders Video catalog $1500 post mci VHS/Beta Regular Catalog choice Mini-Plan $300 Hand-Cut Quality Affordable Price AERODROME MODELS LTD 2623 S Miller Rd Saginaw Ml 48603 OEST 517781-3000 Other kits available Aero-Pacer Baby Pacer Curtias Jenny Flybaby Flybaby Combo Hawker Hurricane h and Jester Stack tar lessiedef Shipment ZENOAII 04237 cu laJ$26495 ZENOAH G23 56ZBNOAH 0-38 96 SACHS 26 TCA 00SACHS 32 TCA 00 SACHS 37 CDI 0SACI4S 37 TCA 00 SACHS 59 CDI 00 SACHS 58 TCA 00 Jim Meseer ERCOUPSPLANS $2396 FULL KIT $23006 JIm MeasrTOMAHAWK PLANS $2396 FULL KIT$23596 Jim Meaaer 13 KIlTEN PLANS $2996 FULL KIT $21996 FLORHO FLYER NIFTY60 kit$5296 FLORIO FLYER 40 kit $7196 FF 00 kIt 6 SUPERFLBX Gasoline tubing /ft. 20/01600 00/$3600 FLOATS 481/4 acale coma $2196 complete kit $4796 10 WW1 WHEELS $3096 P/K Spring Starter 6 PLANS SUPER STEARMAN 1/4 IGodtrayl$2600 1/3 TAYLORCRAFT 1/3 CUB Halite$3096 MGA hinted Pilot Sante 1/4 ax WWI WW2 Civ81996 Sarvo H40242 ox $1296 WoddS.ltforirge modeIa$4496 Prop sines ER TOP FLITE DYNATHRUST 20% off US Ooedme FUEL TANKS16 o $79623 OL FIBERGLASS ARROW SHAFTS 5/16 022 long 0 $1196 24 Hr Service $200 postage Bank Check MO JIM MESSERS QUALITY MODEL PRODUCTS Valley View DrIve. Box 43 Allegeny NY 14700 Radio Technique/Myers Continued page 131 AT CONTEST ground range should ex ceed 300 ft transmitter has section about 8 its antenna exposed An S gnal should grounds refusing fly channel might affected way im age 21M 31M adjacent channel looking signal outside 72-73 MHz band has strength S round should mathematics find out can interact RC transmitter produce image 21M interference wideband SC4SS receivers field has strength S M possibilities should considered Narrow-band dual-conversion receivers should able resist problems signals S low Best defense ground range checks before flight Commencement address scanner trained human brain interpret its findings just noisemaker Now have finished short course trained level beginner Go now learn use scanner find identify interference sources discover something think should added lessons let know about RC Electrics/Kopski Continued page 43 bought warranted 60 months automotive applications also war ranted half deep cycle applications latter means running down way damaging described abovejust what need peace mind during long summer flying sessions Furthermore also learned during re search subject brands warranted normal auto applicationsso watch out What Ive begun routinely now after par ticularly demanding flying session put car charge overnight ordinary house hold auto battery charger have cause routinely go flying night less summer since drives field work about 8-10 minutes length car does have chance re charge battery Folks lessons did come easily cheaply Im glad have opportunity pass info alongfor Electric other flying should fun car wont start isnt Next time have replace auto bat tery keep information mind lot flying relatively little driving consider getting inexpensive household auto-battery charger Incidentally battery brand bought Mega-Tron Speaking charging some perform ance information new Astro model 112 DC/DC Constant Current Charger item discussed June column pictured July photo shows inside view familiar previous model 102 can readily tell different Since earlier mentions Ive chance check out product bench field use First some former tested 112 high-power variable lab supply place auto battery allowed easily simulate varying conditions may found car battery same time used eight-cell 2-Ah pack 20-cell 2-Ah pack charging subjects first test run vary input voltage V0 during charge shown table below check stability 112s output current load also measured input current satisfy curiosity 8-CELL PACK20-CELL PACK volts 110 120 130 140 load amps 363 400* 432 467 amps 578 592 604 616 load amps 318 350* 385 417 amps 1175 1189 1257 1280 conclusion can drawn output current varies proportion put voltage input voltage range tested covers range very low auto battery 110 volts through nominal 120 volts up condition representative engine run ning 140 volts particularly important since auto battery voltage will dinarily change very little during given charge cycle Incidentally * notation above simply means chosen value current starters 120 volts next test charge both packs zero 112 powered constant 120volt source charge current initially set 40 amps purpose test see constant output current load would battery being charged rose terminal volt age V load throughout 15-minute charge time 8-CELL PACK20-CELL PACK Time loadVd loadVjood mmampsvoltsampsvolts 04001190400300 53781250378353 10 385 1367 378 357 15 385 1385 378 360 evaluation shows value current set start charge remains nearly setpoint during charge time period means 112 can set forget far charge current value concerned something could done un modified 102 friends name constant current comes Ive charger field use few weeks has working nicely Ive able load planes car set up charge conditions start up drive field charge planes along way have con nections auto battery rear minivan precaution take set ini tial current about 10% low cause know will rise start car enginejust shown previous table charge-while-I-drive technique new meIve doing years mod ified 102 also charge system own design Frankly its way Id accept charger cause like arrive field two three planes ready go Ive made two other observations 112 timer switch runs 13 minutes 15so Ive compensating little higher current might want time timer just make sure Also 1200-volt put maximum output current available 24-cell pack 36 amps means larger packs cannot charged preferred higher currents must charged cycle time switch must charged cars engine running evident case modified 102 another improvement 112 134 Model Aviation Flash Just Bob Boucher Astro news latest Model 1 t2s off production line upgraded output shown largest packs easily ob tamed Bob tells have first several manufactured can ex pect yours will outperform mineuntil get upgraded course Last month featured rather extensive data formation number OSs forgive give month Id like share some data effects propeller size power de mand gave similar information back No vember 83 MA other props data run Astro 15 cobalt constant put voltage 100 volts first part following data array illus trates effects propeller pitch constant di ameter motor input power chose series Rev-Up props because pitches listed below Propeller Dia Pitch Amps RPM Power inwatts Rev-Up8 31241183124 41451151145 51721110172 61911070191 next data set illustrates same effects ex cept varying propeller diameter constant pitch used Top Flite propsalso cause em Propeller DiaPitchAmpsRPMPower ininwatts Top Flite 64762125276 790122598 81401150140 92071050207 Please note rapidly motor input power creases either both diameter pitch crease Finally data set variety 8 x 4 props size prop very popular days OSs through 1St PropellerAmpsRPMPower 8 x 4 watts Top Flite 140 1150 140 wood Tornado1601115160 plastic Rev-Up1421145142 Top Flite1671107167 nylon Cox Grey1351153135 plastic Zinger1501129150 Master AS1671102167 K&W1571120157 short hub K&W1871075187 long hub What see 8 x 4 props created equal experience prop loads heavier bench demands higher input power also flies plane better shorter So ends another months writing fun Coming up future columns break break some commutator-brush-angle infor mation some motor performance data lots other things Electric Piease forward comment question SASE please address shown above KRC Electric Fly announcement also logo head column Happy quiet Electric landings everyone August 1989 135 AVAILABLE AT AMERICAS DISTRIBUTED ST HOBBY SHOPS SMIflflhi END WE WEIRD iSSO So, Gahnel Rood cadero cA 534 5-1717