George M Myers arm 3d HIcksvIlIe NY 11801 ABSTRACT Alaska single- dual-conversion receivers explained ALASKA Talk about response February issue out week re ceived five letters two phone calls Alas kans challenging perceptions Alaska normal week would get couple letters ask ing questions about radios reread February 89 issue page 35 see what said wrong said No trees except coastal Southeast should have said No trees tundra north Brooks Range rest Alaska has plenty trees also got called permafrost state ment have point government maps say can find permafrost under lit erally everything isnt solid rock Only southern rim including Anchorage generally free permafrost Alaska means Great Land People live intensely proud protective Look pile letters Alaska has moun tains rivers forests lakes some fascinating flora fauna found anywhere world Everything about Alaska differ ent has largest number pilots state USA map Alaska overlaid lower 48 Alaska spreads Savannah GA Duluth MN San Diego Heres better look Dave Unruh George has admit really trees Alaskaespecially after Dave Unruh sent TD Coupe up Kenal AK him photo flying site near Kenal AK Spectacular view AMA AVP District Xi Gary R Fuller sent overiay map Aiaska superimposed Lower 48 tip Aieutian Isiands kind gets lost over Nevada Southern California may bit difficult make out coastal islands over Georgia North end South Carolina Tennessee Did really know Alaska large 36 Model Aviation xl VPAnchora9e0 5 r4l&ILVISOMBtAL *15* 5$ * P5*11 2 N ..jN 1000100200200*00 CA thanks Gary R Fuller AMA District XI AVP up Kotzebue sent two pages Alaskan facts overlay map Dave Un ruh Kenai sent pictures answered bunch questions listed 18 flying sites down middle state Ken Howell presi dent Alaska RC Society Anchorage sent description RC flying Alaska fly ing sites Chuck Dimon sent Ketchi kan Rainbird sticker went right SA 16-like Seabird bunch information things see included telephone num bers offers hospitality sort overwhelming metropolitan dweller like letter really blew away came David Lawrence An excerpt follows information last article really got 11 years have lived Alaska have never noticed perma frost dust hills treeless OK now will serious name David Lawrence am 16 years old have hobby four years Im junior local high school has larger population some small cities work hobby store lo cal shopping mall better stocked lot hobby stores West Coast mall con tains 194 stores no sales tax Let give few true facts about city live Anchorage permafrost dust however active logging dustry trees said did exist summer temperature averages about 75 0 F greatnot too hot too cold As driving 100 miles fly could mistaken central loca tion Anchorage can reach nearest fly ing field 15 minutes nearest Slope site 20 minutes good Glider site 20 minutes No matter what bring fly prepared face off against topnotch pilots vid Lawrence 4140 Kutcher Dr Anchorage AK 99516 Keep eye David Lawrence addition letter sent bundle information Alaska including some pictures youll see next month David wants airline pilot think hell good David already knows Continued page 38 Excellent Career Opportunity Model Aviation growing searching experi enced illustrator/draftsman solid RC modeling background whos capable solving design kit-engineering problems An excellent pay benefit package available think youre just person looking send resume Carl Goldberg Models Inc 4734 W Chicago Ave Chicago IL 60651 Department R Carl Goldberg Models Inc An Equal Opportunity Employer Dent Hornswoggled verY IifelinesYo Th6 ushrod5 f aircraftntrol se COntrol re cantsttanycOhorns efltru operatiofl tO JUve can onsidere tro Horra9d kink nail link iocated wi control Robart gall Link CO tob6flflthe yoU th prec Od5 hthe center iout theWit endO after WIlicatirotatin9 ccLJrate what apPbart0fters bail linkoye less bOY5thean additionn expensi ateneed ur horn elimin d Wh waste yo Pushrontrol systems hen ca efficiefl~ timejth RO art mofHorns Ball Link Contro George thinks Power modelers field box might need dandy little tool kit SR Batteries describes column Robart Mfg 1988PO Box 1247 St Charles Illinois 60174 June 1989 37 EA~ SUITABLE FOR ALL MODELS 112A thru GIANT SIZE Wauconda IL 60084 7e9ee / 54$r / 123 1 Cot thin slot hinge 2 Assemble dry 3 Apply tew drops CA glue youre done history modeling few products wore uly revolutionary example proportional radios on-on coverings CA glues permanently chang ed way build fly models thus quality se revolutionary believe EASY HINGES will have same type impact hobby EASY INGES easy install theyre guaranteed ring smile face first time use 5H710 Pkg 24 $255 MFG CO INCMontezuma IA 50171 VjorldS best 5lliflg Chasm eyran Odnds T&G Mfg uul AM Aircraft Sqiply far its outstuuhg rullalilllty Complete single cyl nder system nc ud ng throttlecoupled spark advance kit spa k spark plug lead25 plug battery pack charger 9O shaded 0 Much kmger inimm Easy haid starts no kickback 1INNI-121N10 RPM reidile 0% power toe suckers om kusteht aviubto Lower piced tush no nitro needed d uk pham teed mat 906 pIng cover FermyenpiesUltp2&4stroke sbagleuultwkacybdsrs zoiprmhactsavddilo 0 Spu* calls spu* phgs slielded plum lead & lha*g kits svaIs some Alaskans say nice thing about Anchorage can drive Alaska Ill try visit everyone especially David al though Kotzebue may Out vans range ways get Anchorage Kotze bue over 1000 miles airplane behind dog team boat water soft Kotzebue 1985 population 2633 near Arctic Circle Bering Sea coast Ive recently read 30 books Alaska including James Micheners Alaska have time read book Alaska recommend Adventuring Alaska Peggy Wayburn Sierra Club book ISBN 087156-787-3 paperback Whats difference between single- double-conversion receivers discussing question Mid-Hudson RC Society used sketch seemed help make dif ference clear Ill share RC channels now nominal 10 kHz wide have Fifty RC channels alter nate 50 PRS channels 1000 kHz 72 MHz 73 MHz spacing between signed channel frequencies 1000 10 kHz Thats easy enough understand isnt Now real world both can move about halfway out assigned frequency z want avoid mutual interference Actually want leave little room error move out less 5 kHz So someone asks what differ ence between wideband narrow-band RC ra dio can tell old wideband channels 20 kHz wide new narrowband channels 10 kHz wide Its really simple Transmitters TX send out radio-frequency en ergy receivers RX take Both TX RX contain crystals control frequen cies transmission reception respectively Its done because cheap reliable way have frequency accuracy Because channels close together frequency RX needs trick separate trick called superheterodyning convenience lets talk about system RC38 72550 MHz TX signal mod ulated control information RX crystal part circuit called Lo cal Oscillator LO tuned 72550 MHz Instead can either 455 MHz above below transmitter have singleconversion 455 kHz IF RX call 5C455 IF stands intermediate frequency sake example chose put LO low TX frequency LO puts out un modulated signal 72550 72095 MHz RX antenna picks up modulated 72550 signal TX signal mixed inside RX unmodulated 72095 gen erated LO sum two 144645 difference between 455 MHz Both new signals carry modula tion control information four signals presented intermediate fre quency amplifier IF has properties long wall terms frequency has narrow gate 455 MHz wall blocks other three signals passes modulated signal 455 MHz no 0003fleSa 10 450ranetna radnas 005005 00 IOa nl,c na 00. sketch scale does have 38 Model Aviation Holds twelve gb-plugs Made tough fuel resistant Protects elements ans m hard knocks Keeps gb-plugs neat organized easy find easy use See favorite Hobby Shop Du-Bro Products Inc Bonner Road old wideband 20-kHz-wide gate make point can see signals will pass through gate modulated 455 difference between LO TX signal way want Now look possibilities 1991 Some body comes air RCl5 0 MHz differently modulated signal example receiver takes signal also mixes before mixtures RC38 minus RCl5 concerns us difference 72550 0 doubly modulated once trans mitter Note process RCl5 trans mitter 72090 acts like LO 72095 worst part result fits through old 20-kHz gate very nicely illustrates 21M 23-channel problem wideband SC45Ss RC38 minus RClS hannels 6044-10I 10mc 5046 440ThOU ThISA H55- 80~ 445ASS 20k4040l both modulated signals passed through IF amp decoded presented servo servo confused mixture modulations have interference becomes problem some wideband SC455 RX RCl5 TX few feet closer airplane RC38 TX test RCL5 signal 2 dBM 5 dBM RC38 signal possible build narrow-band SC455 re ceiver can see gate will have narrower z order exclude unwanted signal 460 MHz another way deal prob lem can move gate dual-conversion receiver does mak ing first conversion gate occur 10700 MHz As can see 23-channel problem disappears Using different LO has separated unwanted mixture signal 510 MHz stead 005 MHz before fact closest unwanted signal now PRS385 72560 MHz Mix LO modulated signal occurs frequency 72560 0 10710 MHz Assuming gate width Hz before gets through first gate look what happens gets sec ond gate second local oscillator operating 11155 MHz puts unwanted signal outside second gate NOW 10 kHz-wide narrow-band gate 6044 6046 4 6065 10POSSIS 1010 601$ 00500l07O i4Ok444d44Sd0l 44810 450 J~ fact can now go back first exam ple put closest adjacent channels PRS 375 385 discover TWO MORE modulated signals going through old wideband 20-kHz gate 445 465 MHz make interference servos didnt show single-conversion exam ple because didnt want confuse discus sion narrow-band dual-conversion receiver re Continued page 157 7YAfG MFG Tigerskin~ WHAT DO YOU CALL THE BEST SHEETING MATERIAL FOR FOAM WING CORES Wing Mfg pioneered foam core wing construction early 60s have used everything tangowood 002 stainless steel sheeting last few years have using pressure laminates evolved R & 0 work Uncle Sam Tigerakins pre-finish high density posterboard material clear laminated plastic film top simply apply contact cement such Styro-Stick adhesive cores sheeting press sheeting onto cores material pliable can easily wrap around leading edges Tigerskins CHECK THESE FEATURES Superior strength weight ratio Superior bond capability foam 001 per sq temperature stability Smooth high gloss finish Superior resistance nitro fuel Superior resistance weather Easy apply Low low cost 01/64 x 23 35 size 1*o 0417 Comes following colors Waco Red Polar White Insignia Blue Sun Yellow $495 PER SHEET RING Send check money order required amount Add $395 shipping 1 6 sheets Add $749 shipping 7 12 sheets SEND TO Wing Mfg PO Box 33 Crystal Lake IL 60014 Illinois Residents add 6 1 /251o sales tax ijI Super Styra-Stick wing skin adhesive $596 16 oz Can Item #601 can does wing up 70 No extra shipping cost ordered Tigerekins See Tigerskens Chicago Model & Hobby Show Booth 1735 SEND $350 FOR CATALOG June 1989 39 Invisible SvitchTM direct replacement radio on/off switch Und Ve Call Der Svitch"5 Der Svitch80 on-board magnetic on/oft switch radio equipment hides inside fuselage activated outside included small bar magnet shown above cut awful holes fuselage. Isnt time made Der Svitcb Ideal Any A/C Plane Boat Car Scale Proiects Wafer Flyers Safe use Consumes no power ation free h resistant atible radio Optional red LED lamp installs plane dash wing indicate radio state Simple Install Futaba Airtronics radios order Model 1402 simply unplug on/off switch plug Der Svitch order Model 1401 use connectors old on/ott switch instructions supplied Der Svitch includes bar magnet activator shown above ModelDescnptionPrice ea 1401Der Svitch activator no connectors twisted leads$1995 1401 LEDDer Svitch activator no connectors twisted leads option leads tor external LED #1405$2495 es 1402*Der Svitch activator connectors tor Futaba Airtronics$2495 es 14O2LEDDer Syitch activator connectors tor Fstaba Airtronics option leads tor esternal LED #1405$2995 ea 1405LEO red lawp w124 twisted leads Models 1401 LED 1402LE0$595 * ordering Model 1402 1402LE0 please specify radio connectortypes Connectors available Futaba J Futaba G Airtronics radios order include name address specify models needed include check money order send Ragan/BarkerGroup 5050 Duorum Drive Suite 741 Dallas Texas 75240 Please add $250 per order cover UPS charges Texas residents add sales tax Credit Card orders call between 9 00 500 Central Time M-F Please allow 2-4 weeks delivery Patent Pending Dealer Inquiries Invited F ininin C/L New R/C HANGAR rn CATALOG IKits OR Plans Innovative Inexpensive Quick&Easy Build HORNET 074 Order yours today QUICK & LIVELY SPORT BIPLARE GREAT FOR SMALL FSELIlS Designed new Cnn 074 Queen See enganel SEND 2 Spenificatinona Wing Spurn 2h Oang Area 275 Sq Length 25 Loading 13 SzSq Pt Weoght 1112 Lb Radio iChannel micro servos Experience aileron trainer qoalofoes yoo tn pilot sleek nk inn airplane Sisple dorahie rentangular 2spar hd noons sheeted box type 0 oselage solid tail surfaces pretot aAA balsa ply tollsize illostrated plana STANGEL ENTERPRISES ostb tooplete instroc non ha dna e pa baghtP 0 BC 36 M MEMBER0 AC LPlunn S4995 01350 ShlI Plan ySSe 95 $150 SSHWAUKESHA WSCONON5 bAMJ tively uncommon sizes /32 hard alu minum sheet landing gear stock small 00-90 0-80 hex screws nuts small 00 1 2 wood screws practi cally everything else available hobby shop worry can ordered National Trea sure Scratch Builders Sig Manufactur ing Company Youll also need small nut-drivers screwdrivers use 21-piece tool set sold Polks Model Craft Hobbies Micro-Mark shown ads fine little tools Scale model builders very reasonable price Whether sound Longsters model four-cycle engine conjures memories favorite full-size airplanes have known flownor merely sounds like model four-cycle enginewith its steady flying habits hybrid lightplane/antique sure please Just remem ber winds blow Longster better go Radio Technique/Myers Continued page 39 jects 23-channel problem AND two adjacent-channel problems exist wideband 5C455 receiver Thats Bob Aberle chose identify dual-conversion narrow-band receiver 1991 receiver Note above refers AM FM Theres no difference between far interference type concerned Larry Sribnick has done again Larry friend firm SR Batteries Inc Box 287 Bellport NY 11713 phone 516/2860079 FAX 516/286-0901 now marketing tool kit consists screwdriver-type han dle ratchet handle assortment /a-in hex-shaft tool bits will also fit electric screwdriver whole shebang comes snaplocked bright yellow plastic case sells $2695 plus $3 shipping handling tool bits fit No 1 2 Phillips-head screws /l6 slotted screws 12 sizes English hex keys 050 through 5/lb six sizes metric hex keys 15mm through 5mm adapter Ia-in square-drive sockets components hardened blackened resist rust except ratchet handle stainless steel screw driver handle plastic tool bits have spring-loaded balls lock place An added setscrew socket screwdriver handle insures wont losing tool bits inside model per feet item tool kit can handle things like wheel collars engine mount bolts etc got set immdediately filed two tabs off screwdriver shaft can slip ratchet handle thereon case need give lit tle extra urge stuck screws Should happen damage tool bit replacements available $1 SR Batteries RC Battle/Good Continued page 45 approved five new 72 MHz channels close 3-to-2 decision two Commission ers absent disconcerting dissenting Commissioners opined RC pears essentially triv ial use does warrant allocation spectrum space Caustic words hairbreadth voting coupled disparaging minority opinion might have undercut optimism about course future battles FCC except Courtneys shrewd analysis counsel explained Commissioners votes di vided sharply according respective years service three favor AMA proposal served 12 15 21 years respectively two voted against three years respective tenure caution ary experience Courtneys view confirmed importance continu ally educating public officials about RC hobby would well heed re minder RC Old-Timers/Mathews Continued page 49 original ignition wiring remained consisted mid-Thirties-type automotive acces sory wire totally deteriorated insulation cracked touch re placed unique double-pole double-throw knife-blade switch disassembled cleaned corrosion buffed installed although its used its original location Although laminated balsa wheels re moved sanded tire area repainted THE LEADER IN COMPETITION NEW 4[L#L SERIES 100 THP DESIGN \ /DIAPRICE 15 16 NEW PRO SERIES 3 \ / i S NEW NIGH TECH AIRFOIL SECTION 10T0200/oINCREASE IN THRUST MFG OF SELECT HARD MAPLE WOOD WILL NOT FATIGUE LIKE SYNTHETICS FUELPROOFHIGH LUSTER FINISH DIAPITCH PRICE 534 634 72633456 6334568 645667 9456677/ 104566A7 106W6W 106EW 114677 7 7 46 ii5W ii6EW 1167 124W 12SW 1256 1356 1456 1556 164/N 16678 RC PYLON RACING SERIES 500 DIA PITCHPRICE 75N 5/N 6I 67/,78 SERIES 400C 9777Io W WIDE BLADE EW EXTRA WIDE N NARROW PROPELLERS TAILORED HELICAL PITCH DEVELOPEDTOGIVE MAXIMUM THRUST AT 4 CYCLE ENGINE RPM ALL THE LATEST TECHNIQUES USED ON OUR PRO SERIES 3 SEE BELOW PITCH THP 66 77 /6 677 6 677 8 67 676 June 1989 157
Edition: Model Aviation - 1989/06
Page Numbers: 36, 37, 38, 39, 157
George M Myers arm 3d HIcksvIlIe NY 11801 ABSTRACT Alaska single- dual-conversion receivers explained ALASKA Talk about response February issue out week re ceived five letters two phone calls Alas kans challenging perceptions Alaska normal week would get couple letters ask ing questions about radios reread February 89 issue page 35 see what said wrong said No trees except coastal Southeast should have said No trees tundra north Brooks Range rest Alaska has plenty trees also got called permafrost state ment have point government maps say can find permafrost under lit erally everything isnt solid rock Only southern rim including Anchorage generally free permafrost Alaska means Great Land People live intensely proud protective Look pile letters Alaska has moun tains rivers forests lakes some fascinating flora fauna found anywhere world Everything about Alaska differ ent has largest number pilots state USA map Alaska overlaid lower 48 Alaska spreads Savannah GA Duluth MN San Diego Heres better look Dave Unruh George has admit really trees Alaskaespecially after Dave Unruh sent TD Coupe up Kenal AK him photo flying site near Kenal AK Spectacular view AMA AVP District Xi Gary R Fuller sent overiay map Aiaska superimposed Lower 48 tip Aieutian Isiands kind gets lost over Nevada Southern California may bit difficult make out coastal islands over Georgia North end South Carolina Tennessee Did really know Alaska large 36 Model Aviation xl VPAnchora9e0 5 r4l&ILVISOMBtAL *15* 5$ * P5*11 2 N ..jN 1000100200200*00 CA thanks Gary R Fuller AMA District XI AVP up Kotzebue sent two pages Alaskan facts overlay map Dave Un ruh Kenai sent pictures answered bunch questions listed 18 flying sites down middle state Ken Howell presi dent Alaska RC Society Anchorage sent description RC flying Alaska fly ing sites Chuck Dimon sent Ketchi kan Rainbird sticker went right SA 16-like Seabird bunch information things see included telephone num bers offers hospitality sort overwhelming metropolitan dweller like letter really blew away came David Lawrence An excerpt follows information last article really got 11 years have lived Alaska have never noticed perma frost dust hills treeless OK now will serious name David Lawrence am 16 years old have hobby four years Im junior local high school has larger population some small cities work hobby store lo cal shopping mall better stocked lot hobby stores West Coast mall con tains 194 stores no sales tax Let give few true facts about city live Anchorage permafrost dust however active logging dustry trees said did exist summer temperature averages about 75 0 F greatnot too hot too cold As driving 100 miles fly could mistaken central loca tion Anchorage can reach nearest fly ing field 15 minutes nearest Slope site 20 minutes good Glider site 20 minutes No matter what bring fly prepared face off against topnotch pilots vid Lawrence 4140 Kutcher Dr Anchorage AK 99516 Keep eye David Lawrence addition letter sent bundle information Alaska including some pictures youll see next month David wants airline pilot think hell good David already knows Continued page 38 Excellent Career Opportunity Model Aviation growing searching experi enced illustrator/draftsman solid RC modeling background whos capable solving design kit-engineering problems An excellent pay benefit package available think youre just person looking send resume Carl Goldberg Models Inc 4734 W Chicago Ave Chicago IL 60651 Department R Carl Goldberg Models Inc An Equal Opportunity Employer Dent Hornswoggled verY IifelinesYo Th6 ushrod5 f aircraftntrol se COntrol re cantsttanycOhorns efltru operatiofl tO JUve can onsidere tro Horra9d kink nail link iocated wi control Robart gall Link CO tob6flflthe yoU th prec Od5 hthe center iout theWit endO after WIlicatirotatin9 ccLJrate what apPbart0fters bail linkoye less bOY5thean additionn expensi ateneed ur horn elimin d Wh waste yo Pushrontrol systems hen ca efficiefl~ timejth RO art mofHorns Ball Link Contro George thinks Power modelers field box might need dandy little tool kit SR Batteries describes column Robart Mfg 1988PO Box 1247 St Charles Illinois 60174 June 1989 37 EA~ SUITABLE FOR ALL MODELS 112A thru GIANT SIZE Wauconda IL 60084 7e9ee / 54$r / 123 1 Cot thin slot hinge 2 Assemble dry 3 Apply tew drops CA glue youre done history modeling few products wore uly revolutionary example proportional radios on-on coverings CA glues permanently chang ed way build fly models thus quality se revolutionary believe EASY HINGES will have same type impact hobby EASY INGES easy install theyre guaranteed ring smile face first time use 5H710 Pkg 24 $255 MFG CO INCMontezuma IA 50171 VjorldS best 5lliflg Chasm eyran Odnds T&G Mfg uul AM Aircraft Sqiply far its outstuuhg rullalilllty Complete single cyl nder system nc ud ng throttlecoupled spark advance kit spa k spark plug lead25 plug battery pack charger 9O shaded 0 Much kmger inimm Easy haid starts no kickback 1INNI-121N10 RPM reidile 0% power toe suckers om kusteht aviubto Lower piced tush no nitro needed d uk pham teed mat 906 pIng cover FermyenpiesUltp2&4stroke sbagleuultwkacybdsrs zoiprmhactsavddilo 0 Spu* calls spu* phgs slielded plum lead & lha*g kits svaIs some Alaskans say nice thing about Anchorage can drive Alaska Ill try visit everyone especially David al though Kotzebue may Out vans range ways get Anchorage Kotze bue over 1000 miles airplane behind dog team boat water soft Kotzebue 1985 population 2633 near Arctic Circle Bering Sea coast Ive recently read 30 books Alaska including James Micheners Alaska have time read book Alaska recommend Adventuring Alaska Peggy Wayburn Sierra Club book ISBN 087156-787-3 paperback Whats difference between single- double-conversion receivers discussing question Mid-Hudson RC Society used sketch seemed help make dif ference clear Ill share RC channels now nominal 10 kHz wide have Fifty RC channels alter nate 50 PRS channels 1000 kHz 72 MHz 73 MHz spacing between signed channel frequencies 1000 10 kHz Thats easy enough understand isnt Now real world both can move about halfway out assigned frequency z want avoid mutual interference Actually want leave little room error move out less 5 kHz So someone asks what differ ence between wideband narrow-band RC ra dio can tell old wideband channels 20 kHz wide new narrowband channels 10 kHz wide Its really simple Transmitters TX send out radio-frequency en ergy receivers RX take Both TX RX contain crystals control frequen cies transmission reception respectively Its done because cheap reliable way have frequency accuracy Because channels close together frequency RX needs trick separate trick called superheterodyning convenience lets talk about system RC38 72550 MHz TX signal mod ulated control information RX crystal part circuit called Lo cal Oscillator LO tuned 72550 MHz Instead can either 455 MHz above below transmitter have singleconversion 455 kHz IF RX call 5C455 IF stands intermediate frequency sake example chose put LO low TX frequency LO puts out un modulated signal 72550 72095 MHz RX antenna picks up modulated 72550 signal TX signal mixed inside RX unmodulated 72095 gen erated LO sum two 144645 difference between 455 MHz Both new signals carry modula tion control information four signals presented intermediate fre quency amplifier IF has properties long wall terms frequency has narrow gate 455 MHz wall blocks other three signals passes modulated signal 455 MHz no 0003fleSa 10 450ranetna radnas 005005 00 IOa nl,c na 00. sketch scale does have 38 Model Aviation Holds twelve gb-plugs Made tough fuel resistant Protects elements ans m hard knocks Keeps gb-plugs neat organized easy find easy use See favorite Hobby Shop Du-Bro Products Inc Bonner Road old wideband 20-kHz-wide gate make point can see signals will pass through gate modulated 455 difference between LO TX signal way want Now look possibilities 1991 Some body comes air RCl5 0 MHz differently modulated signal example receiver takes signal also mixes before mixtures RC38 minus RCl5 concerns us difference 72550 0 doubly modulated once trans mitter Note process RCl5 trans mitter 72090 acts like LO 72095 worst part result fits through old 20-kHz gate very nicely illustrates 21M 23-channel problem wideband SC45Ss RC38 minus RClS hannels 6044-10I 10mc 5046 440ThOU ThISA H55- 80~ 445ASS 20k4040l both modulated signals passed through IF amp decoded presented servo servo confused mixture modulations have interference becomes problem some wideband SC455 RX RCl5 TX few feet closer airplane RC38 TX test RCL5 signal 2 dBM 5 dBM RC38 signal possible build narrow-band SC455 re ceiver can see gate will have narrower z order exclude unwanted signal 460 MHz another way deal prob lem can move gate dual-conversion receiver does mak ing first conversion gate occur 10700 MHz As can see 23-channel problem disappears Using different LO has separated unwanted mixture signal 510 MHz stead 005 MHz before fact closest unwanted signal now PRS385 72560 MHz Mix LO modulated signal occurs frequency 72560 0 10710 MHz Assuming gate width Hz before gets through first gate look what happens gets sec ond gate second local oscillator operating 11155 MHz puts unwanted signal outside second gate NOW 10 kHz-wide narrow-band gate 6044 6046 4 6065 10POSSIS 1010 601$ 00500l07O i4Ok444d44Sd0l 44810 450 J~ fact can now go back first exam ple put closest adjacent channels PRS 375 385 discover TWO MORE modulated signals going through old wideband 20-kHz gate 445 465 MHz make interference servos didnt show single-conversion exam ple because didnt want confuse discus sion narrow-band dual-conversion receiver re Continued page 157 7YAfG MFG Tigerskin~ WHAT DO YOU CALL THE BEST SHEETING MATERIAL FOR FOAM WING CORES Wing Mfg pioneered foam core wing construction early 60s have used everything tangowood 002 stainless steel sheeting last few years have using pressure laminates evolved R & 0 work Uncle Sam Tigerakins pre-finish high density posterboard material clear laminated plastic film top simply apply contact cement such Styro-Stick adhesive cores sheeting press sheeting onto cores material pliable can easily wrap around leading edges Tigerskins CHECK THESE FEATURES Superior strength weight ratio Superior bond capability foam 001 per sq temperature stability Smooth high gloss finish Superior resistance nitro fuel Superior resistance weather Easy apply Low low cost 01/64 x 23 35 size 1*o 0417 Comes following colors Waco Red Polar White Insignia Blue Sun Yellow $495 PER SHEET RING Send check money order required amount Add $395 shipping 1 6 sheets Add $749 shipping 7 12 sheets SEND TO Wing Mfg PO Box 33 Crystal Lake IL 60014 Illinois Residents add 6 1 /251o sales tax ijI Super Styra-Stick wing skin adhesive $596 16 oz Can Item #601 can does wing up 70 No extra shipping cost ordered Tigerekins See Tigerskens Chicago Model & Hobby Show Booth 1735 SEND $350 FOR CATALOG June 1989 39 Invisible SvitchTM direct replacement radio on/off switch Und Ve Call Der Svitch"5 Der Svitch80 on-board magnetic on/oft switch radio equipment hides inside fuselage activated outside included small bar magnet shown above cut awful holes fuselage. Isnt time made Der Svitcb Ideal Any A/C Plane Boat Car Scale Proiects Wafer Flyers Safe use Consumes no power ation free h resistant atible radio Optional red LED lamp installs plane dash wing indicate radio state Simple Install Futaba Airtronics radios order Model 1402 simply unplug on/off switch plug Der Svitch order Model 1401 use connectors old on/ott switch instructions supplied Der Svitch includes bar magnet activator shown above ModelDescnptionPrice ea 1401Der Svitch activator no connectors twisted leads$1995 1401 LEDDer Svitch activator no connectors twisted leads option leads tor external LED #1405$2495 es 1402*Der Svitch activator connectors tor Futaba Airtronics$2495 es 14O2LEDDer Syitch activator connectors tor Fstaba Airtronics option leads tor esternal LED #1405$2995 ea 1405LEO red lawp w124 twisted leads Models 1401 LED 1402LE0$595 * ordering Model 1402 1402LE0 please specify radio connectortypes Connectors available Futaba J Futaba G Airtronics radios order include name address specify models needed include check money order send Ragan/BarkerGroup 5050 Duorum Drive Suite 741 Dallas Texas 75240 Please add $250 per order cover UPS charges Texas residents add sales tax Credit Card orders call between 9 00 500 Central Time M-F Please allow 2-4 weeks delivery Patent Pending Dealer Inquiries Invited F ininin C/L New R/C HANGAR rn CATALOG IKits OR Plans Innovative Inexpensive Quick&Easy Build HORNET 074 Order yours today QUICK & LIVELY SPORT BIPLARE GREAT FOR SMALL FSELIlS Designed new Cnn 074 Queen See enganel SEND 2 Spenificatinona Wing Spurn 2h Oang Area 275 Sq Length 25 Loading 13 SzSq Pt Weoght 1112 Lb Radio iChannel micro servos Experience aileron trainer qoalofoes yoo tn pilot sleek nk inn airplane Sisple dorahie rentangular 2spar hd noons sheeted box type 0 oselage solid tail surfaces pretot aAA balsa ply tollsize illostrated plana STANGEL ENTERPRISES ostb tooplete instroc non ha dna e pa baghtP 0 BC 36 M MEMBER0 AC LPlunn S4995 01350 ShlI Plan ySSe 95 $150 SSHWAUKESHA WSCONON5 bAMJ tively uncommon sizes /32 hard alu minum sheet landing gear stock small 00-90 0-80 hex screws nuts small 00 1 2 wood screws practi cally everything else available hobby shop worry can ordered National Trea sure Scratch Builders Sig Manufactur ing Company Youll also need small nut-drivers screwdrivers use 21-piece tool set sold Polks Model Craft Hobbies Micro-Mark shown ads fine little tools Scale model builders very reasonable price Whether sound Longsters model four-cycle engine conjures memories favorite full-size airplanes have known flownor merely sounds like model four-cycle enginewith its steady flying habits hybrid lightplane/antique sure please Just remem ber winds blow Longster better go Radio Technique/Myers Continued page 39 jects 23-channel problem AND two adjacent-channel problems exist wideband 5C455 receiver Thats Bob Aberle chose identify dual-conversion narrow-band receiver 1991 receiver Note above refers AM FM Theres no difference between far interference type concerned Larry Sribnick has done again Larry friend firm SR Batteries Inc Box 287 Bellport NY 11713 phone 516/2860079 FAX 516/286-0901 now marketing tool kit consists screwdriver-type han dle ratchet handle assortment /a-in hex-shaft tool bits will also fit electric screwdriver whole shebang comes snaplocked bright yellow plastic case sells $2695 plus $3 shipping handling tool bits fit No 1 2 Phillips-head screws /l6 slotted screws 12 sizes English hex keys 050 through 5/lb six sizes metric hex keys 15mm through 5mm adapter Ia-in square-drive sockets components hardened blackened resist rust except ratchet handle stainless steel screw driver handle plastic tool bits have spring-loaded balls lock place An added setscrew socket screwdriver handle insures wont losing tool bits inside model per feet item tool kit can handle things like wheel collars engine mount bolts etc got set immdediately filed two tabs off screwdriver shaft can slip ratchet handle thereon case need give lit tle extra urge stuck screws Should happen damage tool bit replacements available $1 SR Batteries RC Battle/Good Continued page 45 approved five new 72 MHz channels close 3-to-2 decision two Commission ers absent disconcerting dissenting Commissioners opined RC pears essentially triv ial use does warrant allocation spectrum space Caustic words hairbreadth voting coupled disparaging minority opinion might have undercut optimism about course future battles FCC except Courtneys shrewd analysis counsel explained Commissioners votes di vided sharply according respective years service three favor AMA proposal served 12 15 21 years respectively two voted against three years respective tenure caution ary experience Courtneys view confirmed importance continu ally educating public officials about RC hobby would well heed re minder RC Old-Timers/Mathews Continued page 49 original ignition wiring remained consisted mid-Thirties-type automotive acces sory wire totally deteriorated insulation cracked touch re placed unique double-pole double-throw knife-blade switch disassembled cleaned corrosion buffed installed although its used its original location Although laminated balsa wheels re moved sanded tire area repainted THE LEADER IN COMPETITION NEW 4[L#L SERIES 100 THP DESIGN \ /DIAPRICE 15 16 NEW PRO SERIES 3 \ / i S NEW NIGH TECH AIRFOIL SECTION 10T0200/oINCREASE IN THRUST MFG OF SELECT HARD MAPLE WOOD WILL NOT FATIGUE LIKE SYNTHETICS FUELPROOFHIGH LUSTER FINISH DIAPITCH PRICE 534 634 72633456 6334568 645667 9456677/ 104566A7 106W6W 106EW 114677 7 7 46 ii5W ii6EW 1167 124W 12SW 1256 1356 1456 1556 164/N 16678 RC PYLON RACING SERIES 500 DIA PITCHPRICE 75N 5/N 6I 67/,78 SERIES 400C 9777Io W WIDE BLADE EW EXTRA WIDE N NARROW PROPELLERS TAILORED HELICAL PITCH DEVELOPEDTOGIVE MAXIMUM THRUST AT 4 CYCLE ENGINE RPM ALL THE LATEST TECHNIQUES USED ON OUR PRO SERIES 3 SEE BELOW PITCH THP 66 77 /6 677 6 677 8 67 676 June 1989 157
Edition: Model Aviation - 1989/06
Page Numbers: 36, 37, 38, 39, 157
George M Myers arm 3d HIcksvIlIe NY 11801 ABSTRACT Alaska single- dual-conversion receivers explained ALASKA Talk about response February issue out week re ceived five letters two phone calls Alas kans challenging perceptions Alaska normal week would get couple letters ask ing questions about radios reread February 89 issue page 35 see what said wrong said No trees except coastal Southeast should have said No trees tundra north Brooks Range rest Alaska has plenty trees also got called permafrost state ment have point government maps say can find permafrost under lit erally everything isnt solid rock Only southern rim including Anchorage generally free permafrost Alaska means Great Land People live intensely proud protective Look pile letters Alaska has moun tains rivers forests lakes some fascinating flora fauna found anywhere world Everything about Alaska differ ent has largest number pilots state USA map Alaska overlaid lower 48 Alaska spreads Savannah GA Duluth MN San Diego Heres better look Dave Unruh George has admit really trees Alaskaespecially after Dave Unruh sent TD Coupe up Kenal AK him photo flying site near Kenal AK Spectacular view AMA AVP District Xi Gary R Fuller sent overiay map Aiaska superimposed Lower 48 tip Aieutian Isiands kind gets lost over Nevada Southern California may bit difficult make out coastal islands over Georgia North end South Carolina Tennessee Did really know Alaska large 36 Model Aviation xl VPAnchora9e0 5 r4l&ILVISOMBtAL *15* 5$ * P5*11 2 N ..jN 1000100200200*00 CA thanks Gary R Fuller AMA District XI AVP up Kotzebue sent two pages Alaskan facts overlay map Dave Un ruh Kenai sent pictures answered bunch questions listed 18 flying sites down middle state Ken Howell presi dent Alaska RC Society Anchorage sent description RC flying Alaska fly ing sites Chuck Dimon sent Ketchi kan Rainbird sticker went right SA 16-like Seabird bunch information things see included telephone num bers offers hospitality sort overwhelming metropolitan dweller like letter really blew away came David Lawrence An excerpt follows information last article really got 11 years have lived Alaska have never noticed perma frost dust hills treeless OK now will serious name David Lawrence am 16 years old have hobby four years Im junior local high school has larger population some small cities work hobby store lo cal shopping mall better stocked lot hobby stores West Coast mall con tains 194 stores no sales tax Let give few true facts about city live Anchorage permafrost dust however active logging dustry trees said did exist summer temperature averages about 75 0 F greatnot too hot too cold As driving 100 miles fly could mistaken central loca tion Anchorage can reach nearest fly ing field 15 minutes nearest Slope site 20 minutes good Glider site 20 minutes No matter what bring fly prepared face off against topnotch pilots vid Lawrence 4140 Kutcher Dr Anchorage AK 99516 Keep eye David Lawrence addition letter sent bundle information Alaska including some pictures youll see next month David wants airline pilot think hell good David already knows Continued page 38 Excellent Career Opportunity Model Aviation growing searching experi enced illustrator/draftsman solid RC modeling background whos capable solving design kit-engineering problems An excellent pay benefit package available think youre just person looking send resume Carl Goldberg Models Inc 4734 W Chicago Ave Chicago IL 60651 Department R Carl Goldberg Models Inc An Equal Opportunity Employer Dent Hornswoggled verY IifelinesYo Th6 ushrod5 f aircraftntrol se COntrol re cantsttanycOhorns efltru operatiofl tO JUve can onsidere tro Horra9d kink nail link iocated wi control Robart gall Link CO tob6flflthe yoU th prec Od5 hthe center iout theWit endO after WIlicatirotatin9 ccLJrate what apPbart0fters bail linkoye less bOY5thean additionn expensi ateneed ur horn elimin d Wh waste yo Pushrontrol systems hen ca efficiefl~ timejth RO art mofHorns Ball Link Contro George thinks Power modelers field box might need dandy little tool kit SR Batteries describes column Robart Mfg 1988PO Box 1247 St Charles Illinois 60174 June 1989 37 EA~ SUITABLE FOR ALL MODELS 112A thru GIANT SIZE Wauconda IL 60084 7e9ee / 54$r / 123 1 Cot thin slot hinge 2 Assemble dry 3 Apply tew drops CA glue youre done history modeling few products wore uly revolutionary example proportional radios on-on coverings CA glues permanently chang ed way build fly models thus quality se revolutionary believe EASY HINGES will have same type impact hobby EASY INGES easy install theyre guaranteed ring smile face first time use 5H710 Pkg 24 $255 MFG CO INCMontezuma IA 50171 VjorldS best 5lliflg Chasm eyran Odnds T&G Mfg uul AM Aircraft Sqiply far its outstuuhg rullalilllty Complete single cyl nder system nc ud ng throttlecoupled spark advance kit spa k spark plug lead25 plug battery pack charger 9O shaded 0 Much kmger inimm Easy haid starts no kickback 1INNI-121N10 RPM reidile 0% power toe suckers om kusteht aviubto Lower piced tush no nitro needed d uk pham teed mat 906 pIng cover FermyenpiesUltp2&4stroke sbagleuultwkacybdsrs zoiprmhactsavddilo 0 Spu* calls spu* phgs slielded plum lead & lha*g kits svaIs some Alaskans say nice thing about Anchorage can drive Alaska Ill try visit everyone especially David al though Kotzebue may Out vans range ways get Anchorage Kotze bue over 1000 miles airplane behind dog team boat water soft Kotzebue 1985 population 2633 near Arctic Circle Bering Sea coast Ive recently read 30 books Alaska including James Micheners Alaska have time read book Alaska recommend Adventuring Alaska Peggy Wayburn Sierra Club book ISBN 087156-787-3 paperback Whats difference between single- double-conversion receivers discussing question Mid-Hudson RC Society used sketch seemed help make dif ference clear Ill share RC channels now nominal 10 kHz wide have Fifty RC channels alter nate 50 PRS channels 1000 kHz 72 MHz 73 MHz spacing between signed channel frequencies 1000 10 kHz Thats easy enough understand isnt Now real world both can move about halfway out assigned frequency z want avoid mutual interference Actually want leave little room error move out less 5 kHz So someone asks what differ ence between wideband narrow-band RC ra dio can tell old wideband channels 20 kHz wide new narrowband channels 10 kHz wide Its really simple Transmitters TX send out radio-frequency en ergy receivers RX take Both TX RX contain crystals control frequen cies transmission reception respectively Its done because cheap reliable way have frequency accuracy Because channels close together frequency RX needs trick separate trick called superheterodyning convenience lets talk about system RC38 72550 MHz TX signal mod ulated control information RX crystal part circuit called Lo cal Oscillator LO tuned 72550 MHz Instead can either 455 MHz above below transmitter have singleconversion 455 kHz IF RX call 5C455 IF stands intermediate frequency sake example chose put LO low TX frequency LO puts out un modulated signal 72550 72095 MHz RX antenna picks up modulated 72550 signal TX signal mixed inside RX unmodulated 72095 gen erated LO sum two 144645 difference between 455 MHz Both new signals carry modula tion control information four signals presented intermediate fre quency amplifier IF has properties long wall terms frequency has narrow gate 455 MHz wall blocks other three signals passes modulated signal 455 MHz no 0003fleSa 10 450ranetna radnas 005005 00 IOa nl,c na 00. sketch scale does have 38 Model Aviation Holds twelve gb-plugs Made tough fuel resistant Protects elements ans m hard knocks Keeps gb-plugs neat organized easy find easy use See favorite Hobby Shop Du-Bro Products Inc Bonner Road old wideband 20-kHz-wide gate make point can see signals will pass through gate modulated 455 difference between LO TX signal way want Now look possibilities 1991 Some body comes air RCl5 0 MHz differently modulated signal example receiver takes signal also mixes before mixtures RC38 minus RCl5 concerns us difference 72550 0 doubly modulated once trans mitter Note process RCl5 trans mitter 72090 acts like LO 72095 worst part result fits through old 20-kHz gate very nicely illustrates 21M 23-channel problem wideband SC45Ss RC38 minus RClS hannels 6044-10I 10mc 5046 440ThOU ThISA H55- 80~ 445ASS 20k4040l both modulated signals passed through IF amp decoded presented servo servo confused mixture modulations have interference becomes problem some wideband SC455 RX RCl5 TX few feet closer airplane RC38 TX test RCL5 signal 2 dBM 5 dBM RC38 signal possible build narrow-band SC455 re ceiver can see gate will have narrower z order exclude unwanted signal 460 MHz another way deal prob lem can move gate dual-conversion receiver does mak ing first conversion gate occur 10700 MHz As can see 23-channel problem disappears Using different LO has separated unwanted mixture signal 510 MHz stead 005 MHz before fact closest unwanted signal now PRS385 72560 MHz Mix LO modulated signal occurs frequency 72560 0 10710 MHz Assuming gate width Hz before gets through first gate look what happens gets sec ond gate second local oscillator operating 11155 MHz puts unwanted signal outside second gate NOW 10 kHz-wide narrow-band gate 6044 6046 4 6065 10POSSIS 1010 601$ 00500l07O i4Ok444d44Sd0l 44810 450 J~ fact can now go back first exam ple put closest adjacent channels PRS 375 385 discover TWO MORE modulated signals going through old wideband 20-kHz gate 445 465 MHz make interference servos didnt show single-conversion exam ple because didnt want confuse discus sion narrow-band dual-conversion receiver re Continued page 157 7YAfG MFG Tigerskin~ WHAT DO YOU CALL THE BEST SHEETING MATERIAL FOR FOAM WING CORES Wing Mfg pioneered foam core wing construction early 60s have used everything tangowood 002 stainless steel sheeting last few years have using pressure laminates evolved R & 0 work Uncle Sam Tigerakins pre-finish high density posterboard material clear laminated plastic film top simply apply contact cement such Styro-Stick adhesive cores sheeting press sheeting onto cores material pliable can easily wrap around leading edges Tigerskins CHECK THESE FEATURES Superior strength weight ratio Superior bond capability foam 001 per sq temperature stability Smooth high gloss finish Superior resistance nitro fuel Superior resistance weather Easy apply Low low cost 01/64 x 23 35 size 1*o 0417 Comes following colors Waco Red Polar White Insignia Blue Sun Yellow $495 PER SHEET RING Send check money order required amount Add $395 shipping 1 6 sheets Add $749 shipping 7 12 sheets SEND TO Wing Mfg PO Box 33 Crystal Lake IL 60014 Illinois Residents add 6 1 /251o sales tax ijI Super Styra-Stick wing skin adhesive $596 16 oz Can Item #601 can does wing up 70 No extra shipping cost ordered Tigerekins See Tigerskens Chicago Model & Hobby Show Booth 1735 SEND $350 FOR CATALOG June 1989 39 Invisible SvitchTM direct replacement radio on/off switch Und Ve Call Der Svitch"5 Der Svitch80 on-board magnetic on/oft switch radio equipment hides inside fuselage activated outside included small bar magnet shown above cut awful holes fuselage. Isnt time made Der Svitcb Ideal Any A/C Plane Boat Car Scale Proiects Wafer Flyers Safe use Consumes no power ation free h resistant atible radio Optional red LED lamp installs plane dash wing indicate radio state Simple Install Futaba Airtronics radios order Model 1402 simply unplug on/off switch plug Der Svitch order Model 1401 use connectors old on/ott switch instructions supplied Der Svitch includes bar magnet activator shown above ModelDescnptionPrice ea 1401Der Svitch activator no connectors twisted leads$1995 1401 LEDDer Svitch activator no connectors twisted leads option leads tor external LED #1405$2495 es 1402*Der Svitch activator connectors tor Futaba Airtronics$2495 es 14O2LEDDer Syitch activator connectors tor Fstaba Airtronics option leads tor esternal LED #1405$2995 ea 1405LEO red lawp w124 twisted leads Models 1401 LED 1402LE0$595 * ordering Model 1402 1402LE0 please specify radio connectortypes Connectors available Futaba J Futaba G Airtronics radios order include name address specify models needed include check money order send Ragan/BarkerGroup 5050 Duorum Drive Suite 741 Dallas Texas 75240 Please add $250 per order cover UPS charges Texas residents add sales tax Credit Card orders call between 9 00 500 Central Time M-F Please allow 2-4 weeks delivery Patent Pending Dealer Inquiries Invited F ininin C/L New R/C HANGAR rn CATALOG IKits OR Plans Innovative Inexpensive Quick&Easy Build HORNET 074 Order yours today QUICK & LIVELY SPORT BIPLARE GREAT FOR SMALL FSELIlS Designed new Cnn 074 Queen See enganel SEND 2 Spenificatinona Wing Spurn 2h Oang Area 275 Sq Length 25 Loading 13 SzSq Pt Weoght 1112 Lb Radio iChannel micro servos Experience aileron trainer qoalofoes yoo tn pilot sleek nk inn airplane Sisple dorahie rentangular 2spar hd noons sheeted box type 0 oselage solid tail surfaces pretot aAA balsa ply tollsize illostrated plana STANGEL ENTERPRISES ostb tooplete instroc non ha dna e pa baghtP 0 BC 36 M MEMBER0 AC LPlunn S4995 01350 ShlI Plan ySSe 95 $150 SSHWAUKESHA WSCONON5 bAMJ tively uncommon sizes /32 hard alu minum sheet landing gear stock small 00-90 0-80 hex screws nuts small 00 1 2 wood screws practi cally everything else available hobby shop worry can ordered National Trea sure Scratch Builders Sig Manufactur ing Company Youll also need small nut-drivers screwdrivers use 21-piece tool set sold Polks Model Craft Hobbies Micro-Mark shown ads fine little tools Scale model builders very reasonable price Whether sound Longsters model four-cycle engine conjures memories favorite full-size airplanes have known flownor merely sounds like model four-cycle enginewith its steady flying habits hybrid lightplane/antique sure please Just remem ber winds blow Longster better go Radio Technique/Myers Continued page 39 jects 23-channel problem AND two adjacent-channel problems exist wideband 5C455 receiver Thats Bob Aberle chose identify dual-conversion narrow-band receiver 1991 receiver Note above refers AM FM Theres no difference between far interference type concerned Larry Sribnick has done again Larry friend firm SR Batteries Inc Box 287 Bellport NY 11713 phone 516/2860079 FAX 516/286-0901 now marketing tool kit consists screwdriver-type han dle ratchet handle assortment /a-in hex-shaft tool bits will also fit electric screwdriver whole shebang comes snaplocked bright yellow plastic case sells $2695 plus $3 shipping handling tool bits fit No 1 2 Phillips-head screws /l6 slotted screws 12 sizes English hex keys 050 through 5/lb six sizes metric hex keys 15mm through 5mm adapter Ia-in square-drive sockets components hardened blackened resist rust except ratchet handle stainless steel screw driver handle plastic tool bits have spring-loaded balls lock place An added setscrew socket screwdriver handle insures wont losing tool bits inside model per feet item tool kit can handle things like wheel collars engine mount bolts etc got set immdediately filed two tabs off screwdriver shaft can slip ratchet handle thereon case need give lit tle extra urge stuck screws Should happen damage tool bit replacements available $1 SR Batteries RC Battle/Good Continued page 45 approved five new 72 MHz channels close 3-to-2 decision two Commission ers absent disconcerting dissenting Commissioners opined RC pears essentially triv ial use does warrant allocation spectrum space Caustic words hairbreadth voting coupled disparaging minority opinion might have undercut optimism about course future battles FCC except Courtneys shrewd analysis counsel explained Commissioners votes di vided sharply according respective years service three favor AMA proposal served 12 15 21 years respectively two voted against three years respective tenure caution ary experience Courtneys view confirmed importance continu ally educating public officials about RC hobby would well heed re minder RC Old-Timers/Mathews Continued page 49 original ignition wiring remained consisted mid-Thirties-type automotive acces sory wire totally deteriorated insulation cracked touch re placed unique double-pole double-throw knife-blade switch disassembled cleaned corrosion buffed installed although its used its original location Although laminated balsa wheels re moved sanded tire area repainted THE LEADER IN COMPETITION NEW 4[L#L SERIES 100 THP DESIGN \ /DIAPRICE 15 16 NEW PRO SERIES 3 \ / i S NEW NIGH TECH AIRFOIL SECTION 10T0200/oINCREASE IN THRUST MFG OF SELECT HARD MAPLE WOOD WILL NOT FATIGUE LIKE SYNTHETICS FUELPROOFHIGH LUSTER FINISH DIAPITCH PRICE 534 634 72633456 6334568 645667 9456677/ 104566A7 106W6W 106EW 114677 7 7 46 ii5W ii6EW 1167 124W 12SW 1256 1356 1456 1556 164/N 16678 RC PYLON RACING SERIES 500 DIA PITCHPRICE 75N 5/N 6I 67/,78 SERIES 400C 9777Io W WIDE BLADE EW EXTRA WIDE N NARROW PROPELLERS TAILORED HELICAL PITCH DEVELOPEDTOGIVE MAXIMUM THRUST AT 4 CYCLE ENGINE RPM ALL THE LATEST TECHNIQUES USED ON OUR PRO SERIES 3 SEE BELOW PITCH THP 66 77 /6 677 6 677 8 67 676 June 1989 157
Edition: Model Aviation - 1989/06
Page Numbers: 36, 37, 38, 39, 157
George M Myers arm 3d HIcksvIlIe NY 11801 ABSTRACT Alaska single- dual-conversion receivers explained ALASKA Talk about response February issue out week re ceived five letters two phone calls Alas kans challenging perceptions Alaska normal week would get couple letters ask ing questions about radios reread February 89 issue page 35 see what said wrong said No trees except coastal Southeast should have said No trees tundra north Brooks Range rest Alaska has plenty trees also got called permafrost state ment have point government maps say can find permafrost under lit erally everything isnt solid rock Only southern rim including Anchorage generally free permafrost Alaska means Great Land People live intensely proud protective Look pile letters Alaska has moun tains rivers forests lakes some fascinating flora fauna found anywhere world Everything about Alaska differ ent has largest number pilots state USA map Alaska overlaid lower 48 Alaska spreads Savannah GA Duluth MN San Diego Heres better look Dave Unruh George has admit really trees Alaskaespecially after Dave Unruh sent TD Coupe up Kenal AK him photo flying site near Kenal AK Spectacular view AMA AVP District Xi Gary R Fuller sent overiay map Aiaska superimposed Lower 48 tip Aieutian Isiands kind gets lost over Nevada Southern California may bit difficult make out coastal islands over Georgia North end South Carolina Tennessee Did really know Alaska large 36 Model Aviation xl VPAnchora9e0 5 r4l&ILVISOMBtAL *15* 5$ * P5*11 2 N ..jN 1000100200200*00 CA thanks Gary R Fuller AMA District XI AVP up Kotzebue sent two pages Alaskan facts overlay map Dave Un ruh Kenai sent pictures answered bunch questions listed 18 flying sites down middle state Ken Howell presi dent Alaska RC Society Anchorage sent description RC flying Alaska fly ing sites Chuck Dimon sent Ketchi kan Rainbird sticker went right SA 16-like Seabird bunch information things see included telephone num bers offers hospitality sort overwhelming metropolitan dweller like letter really blew away came David Lawrence An excerpt follows information last article really got 11 years have lived Alaska have never noticed perma frost dust hills treeless OK now will serious name David Lawrence am 16 years old have hobby four years Im junior local high school has larger population some small cities work hobby store lo cal shopping mall better stocked lot hobby stores West Coast mall con tains 194 stores no sales tax Let give few true facts about city live Anchorage permafrost dust however active logging dustry trees said did exist summer temperature averages about 75 0 F greatnot too hot too cold As driving 100 miles fly could mistaken central loca tion Anchorage can reach nearest fly ing field 15 minutes nearest Slope site 20 minutes good Glider site 20 minutes No matter what bring fly prepared face off against topnotch pilots vid Lawrence 4140 Kutcher Dr Anchorage AK 99516 Keep eye David Lawrence addition letter sent bundle information Alaska including some pictures youll see next month David wants airline pilot think hell good David already knows Continued page 38 Excellent Career Opportunity Model Aviation growing searching experi enced illustrator/draftsman solid RC modeling background whos capable solving design kit-engineering problems An excellent pay benefit package available think youre just person looking send resume Carl Goldberg Models Inc 4734 W Chicago Ave Chicago IL 60651 Department R Carl Goldberg Models Inc An Equal Opportunity Employer Dent Hornswoggled verY IifelinesYo Th6 ushrod5 f aircraftntrol se COntrol re cantsttanycOhorns efltru operatiofl tO JUve can onsidere tro Horra9d kink nail link iocated wi control Robart gall Link CO tob6flflthe yoU th prec Od5 hthe center iout theWit endO after WIlicatirotatin9 ccLJrate what apPbart0fters bail linkoye less bOY5thean additionn expensi ateneed ur horn elimin d Wh waste yo Pushrontrol systems hen ca efficiefl~ timejth RO art mofHorns Ball Link Contro George thinks Power modelers field box might need dandy little tool kit SR Batteries describes column Robart Mfg 1988PO Box 1247 St Charles Illinois 60174 June 1989 37 EA~ SUITABLE FOR ALL MODELS 112A thru GIANT SIZE Wauconda IL 60084 7e9ee / 54$r / 123 1 Cot thin slot hinge 2 Assemble dry 3 Apply tew drops CA glue youre done history modeling few products wore uly revolutionary example proportional radios on-on coverings CA glues permanently chang ed way build fly models thus quality se revolutionary believe EASY HINGES will have same type impact hobby EASY INGES easy install theyre guaranteed ring smile face first time use 5H710 Pkg 24 $255 MFG CO INCMontezuma IA 50171 VjorldS best 5lliflg Chasm eyran Odnds T&G Mfg uul AM Aircraft Sqiply far its outstuuhg rullalilllty Complete single cyl nder system nc ud ng throttlecoupled spark advance kit spa k spark plug lead25 plug battery pack charger 9O shaded 0 Much kmger inimm Easy haid starts no kickback 1INNI-121N10 RPM reidile 0% power toe suckers om kusteht aviubto Lower piced tush no nitro needed d uk pham teed mat 906 pIng cover FermyenpiesUltp2&4stroke sbagleuultwkacybdsrs zoiprmhactsavddilo 0 Spu* calls spu* phgs slielded plum lead & lha*g kits svaIs some Alaskans say nice thing about Anchorage can drive Alaska Ill try visit everyone especially David al though Kotzebue may Out vans range ways get Anchorage Kotze bue over 1000 miles airplane behind dog team boat water soft Kotzebue 1985 population 2633 near Arctic Circle Bering Sea coast Ive recently read 30 books Alaska including James Micheners Alaska have time read book Alaska recommend Adventuring Alaska Peggy Wayburn Sierra Club book ISBN 087156-787-3 paperback Whats difference between single- double-conversion receivers discussing question Mid-Hudson RC Society used sketch seemed help make dif ference clear Ill share RC channels now nominal 10 kHz wide have Fifty RC channels alter nate 50 PRS channels 1000 kHz 72 MHz 73 MHz spacing between signed channel frequencies 1000 10 kHz Thats easy enough understand isnt Now real world both can move about halfway out assigned frequency z want avoid mutual interference Actually want leave little room error move out less 5 kHz So someone asks what differ ence between wideband narrow-band RC ra dio can tell old wideband channels 20 kHz wide new narrowband channels 10 kHz wide Its really simple Transmitters TX send out radio-frequency en ergy receivers RX take Both TX RX contain crystals control frequen cies transmission reception respectively Its done because cheap reliable way have frequency accuracy Because channels close together frequency RX needs trick separate trick called superheterodyning convenience lets talk about system RC38 72550 MHz TX signal mod ulated control information RX crystal part circuit called Lo cal Oscillator LO tuned 72550 MHz Instead can either 455 MHz above below transmitter have singleconversion 455 kHz IF RX call 5C455 IF stands intermediate frequency sake example chose put LO low TX frequency LO puts out un modulated signal 72550 72095 MHz RX antenna picks up modulated 72550 signal TX signal mixed inside RX unmodulated 72095 gen erated LO sum two 144645 difference between 455 MHz Both new signals carry modula tion control information four signals presented intermediate fre quency amplifier IF has properties long wall terms frequency has narrow gate 455 MHz wall blocks other three signals passes modulated signal 455 MHz no 0003fleSa 10 450ranetna radnas 005005 00 IOa nl,c na 00. sketch scale does have 38 Model Aviation Holds twelve gb-plugs Made tough fuel resistant Protects elements ans m hard knocks Keeps gb-plugs neat organized easy find easy use See favorite Hobby Shop Du-Bro Products Inc Bonner Road old wideband 20-kHz-wide gate make point can see signals will pass through gate modulated 455 difference between LO TX signal way want Now look possibilities 1991 Some body comes air RCl5 0 MHz differently modulated signal example receiver takes signal also mixes before mixtures RC38 minus RCl5 concerns us difference 72550 0 doubly modulated once trans mitter Note process RCl5 trans mitter 72090 acts like LO 72095 worst part result fits through old 20-kHz gate very nicely illustrates 21M 23-channel problem wideband SC45Ss RC38 minus RClS hannels 6044-10I 10mc 5046 440ThOU ThISA H55- 80~ 445ASS 20k4040l both modulated signals passed through IF amp decoded presented servo servo confused mixture modulations have interference becomes problem some wideband SC455 RX RCl5 TX few feet closer airplane RC38 TX test RCL5 signal 2 dBM 5 dBM RC38 signal possible build narrow-band SC455 re ceiver can see gate will have narrower z order exclude unwanted signal 460 MHz another way deal prob lem can move gate dual-conversion receiver does mak ing first conversion gate occur 10700 MHz As can see 23-channel problem disappears Using different LO has separated unwanted mixture signal 510 MHz stead 005 MHz before fact closest unwanted signal now PRS385 72560 MHz Mix LO modulated signal occurs frequency 72560 0 10710 MHz Assuming gate width Hz before gets through first gate look what happens gets sec ond gate second local oscillator operating 11155 MHz puts unwanted signal outside second gate NOW 10 kHz-wide narrow-band gate 6044 6046 4 6065 10POSSIS 1010 601$ 00500l07O i4Ok444d44Sd0l 44810 450 J~ fact can now go back first exam ple put closest adjacent channels PRS 375 385 discover TWO MORE modulated signals going through old wideband 20-kHz gate 445 465 MHz make interference servos didnt show single-conversion exam ple because didnt want confuse discus sion narrow-band dual-conversion receiver re Continued page 157 7YAfG MFG Tigerskin~ WHAT DO YOU CALL THE BEST SHEETING MATERIAL FOR FOAM WING CORES Wing Mfg pioneered foam core wing construction early 60s have used everything tangowood 002 stainless steel sheeting last few years have using pressure laminates evolved R & 0 work Uncle Sam Tigerakins pre-finish high density posterboard material clear laminated plastic film top simply apply contact cement such Styro-Stick adhesive cores sheeting press sheeting onto cores material pliable can easily wrap around leading edges Tigerskins CHECK THESE FEATURES Superior strength weight ratio Superior bond capability foam 001 per sq temperature stability Smooth high gloss finish Superior resistance nitro fuel Superior resistance weather Easy apply Low low cost 01/64 x 23 35 size 1*o 0417 Comes following colors Waco Red Polar White Insignia Blue Sun Yellow $495 PER SHEET RING Send check money order required amount Add $395 shipping 1 6 sheets Add $749 shipping 7 12 sheets SEND TO Wing Mfg PO Box 33 Crystal Lake IL 60014 Illinois Residents add 6 1 /251o sales tax ijI Super Styra-Stick wing skin adhesive $596 16 oz Can Item #601 can does wing up 70 No extra shipping cost ordered Tigerekins See Tigerskens Chicago Model & Hobby Show Booth 1735 SEND $350 FOR CATALOG June 1989 39 Invisible SvitchTM direct replacement radio on/off switch Und Ve Call Der Svitch"5 Der Svitch80 on-board magnetic on/oft switch radio equipment hides inside fuselage activated outside included small bar magnet shown above cut awful holes fuselage. Isnt time made Der Svitcb Ideal Any A/C Plane Boat Car Scale Proiects Wafer Flyers Safe use Consumes no power ation free h resistant atible radio Optional red LED lamp installs plane dash wing indicate radio state Simple Install Futaba Airtronics radios order Model 1402 simply unplug on/off switch plug Der Svitch order Model 1401 use connectors old on/ott switch instructions supplied Der Svitch includes bar magnet activator shown above ModelDescnptionPrice ea 1401Der Svitch activator no connectors twisted leads$1995 1401 LEDDer Svitch activator no connectors twisted leads option leads tor external LED #1405$2495 es 1402*Der Svitch activator connectors tor Futaba Airtronics$2495 es 14O2LEDDer Syitch activator connectors tor Fstaba Airtronics option leads tor esternal LED #1405$2995 ea 1405LEO red lawp w124 twisted leads Models 1401 LED 1402LE0$595 * ordering Model 1402 1402LE0 please specify radio connectortypes Connectors available Futaba J Futaba G Airtronics radios order include name address specify models needed include check money order send Ragan/BarkerGroup 5050 Duorum Drive Suite 741 Dallas Texas 75240 Please add $250 per order cover UPS charges Texas residents add sales tax Credit Card orders call between 9 00 500 Central Time M-F Please allow 2-4 weeks delivery Patent Pending Dealer Inquiries Invited F ininin C/L New R/C HANGAR rn CATALOG IKits OR Plans Innovative Inexpensive Quick&Easy Build HORNET 074 Order yours today QUICK & LIVELY SPORT BIPLARE GREAT FOR SMALL FSELIlS Designed new Cnn 074 Queen See enganel SEND 2 Spenificatinona Wing Spurn 2h Oang Area 275 Sq Length 25 Loading 13 SzSq Pt Weoght 1112 Lb Radio iChannel micro servos Experience aileron trainer qoalofoes yoo tn pilot sleek nk inn airplane Sisple dorahie rentangular 2spar hd noons sheeted box type 0 oselage solid tail surfaces pretot aAA balsa ply tollsize illostrated plana STANGEL ENTERPRISES ostb tooplete instroc non ha dna e pa baghtP 0 BC 36 M MEMBER0 AC LPlunn S4995 01350 ShlI Plan ySSe 95 $150 SSHWAUKESHA WSCONON5 bAMJ tively uncommon sizes /32 hard alu minum sheet landing gear stock small 00-90 0-80 hex screws nuts small 00 1 2 wood screws practi cally everything else available hobby shop worry can ordered National Trea sure Scratch Builders Sig Manufactur ing Company Youll also need small nut-drivers screwdrivers use 21-piece tool set sold Polks Model Craft Hobbies Micro-Mark shown ads fine little tools Scale model builders very reasonable price Whether sound Longsters model four-cycle engine conjures memories favorite full-size airplanes have known flownor merely sounds like model four-cycle enginewith its steady flying habits hybrid lightplane/antique sure please Just remem ber winds blow Longster better go Radio Technique/Myers Continued page 39 jects 23-channel problem AND two adjacent-channel problems exist wideband 5C455 receiver Thats Bob Aberle chose identify dual-conversion narrow-band receiver 1991 receiver Note above refers AM FM Theres no difference between far interference type concerned Larry Sribnick has done again Larry friend firm SR Batteries Inc Box 287 Bellport NY 11713 phone 516/2860079 FAX 516/286-0901 now marketing tool kit consists screwdriver-type han dle ratchet handle assortment /a-in hex-shaft tool bits will also fit electric screwdriver whole shebang comes snaplocked bright yellow plastic case sells $2695 plus $3 shipping handling tool bits fit No 1 2 Phillips-head screws /l6 slotted screws 12 sizes English hex keys 050 through 5/lb six sizes metric hex keys 15mm through 5mm adapter Ia-in square-drive sockets components hardened blackened resist rust except ratchet handle stainless steel screw driver handle plastic tool bits have spring-loaded balls lock place An added setscrew socket screwdriver handle insures wont losing tool bits inside model per feet item tool kit can handle things like wheel collars engine mount bolts etc got set immdediately filed two tabs off screwdriver shaft can slip ratchet handle thereon case need give lit tle extra urge stuck screws Should happen damage tool bit replacements available $1 SR Batteries RC Battle/Good Continued page 45 approved five new 72 MHz channels close 3-to-2 decision two Commission ers absent disconcerting dissenting Commissioners opined RC pears essentially triv ial use does warrant allocation spectrum space Caustic words hairbreadth voting coupled disparaging minority opinion might have undercut optimism about course future battles FCC except Courtneys shrewd analysis counsel explained Commissioners votes di vided sharply according respective years service three favor AMA proposal served 12 15 21 years respectively two voted against three years respective tenure caution ary experience Courtneys view confirmed importance continu ally educating public officials about RC hobby would well heed re minder RC Old-Timers/Mathews Continued page 49 original ignition wiring remained consisted mid-Thirties-type automotive acces sory wire totally deteriorated insulation cracked touch re placed unique double-pole double-throw knife-blade switch disassembled cleaned corrosion buffed installed although its used its original location Although laminated balsa wheels re moved sanded tire area repainted THE LEADER IN COMPETITION NEW 4[L#L SERIES 100 THP DESIGN \ /DIAPRICE 15 16 NEW PRO SERIES 3 \ / i S NEW NIGH TECH AIRFOIL SECTION 10T0200/oINCREASE IN THRUST MFG OF SELECT HARD MAPLE WOOD WILL NOT FATIGUE LIKE SYNTHETICS FUELPROOFHIGH LUSTER FINISH DIAPITCH PRICE 534 634 72633456 6334568 645667 9456677/ 104566A7 106W6W 106EW 114677 7 7 46 ii5W ii6EW 1167 124W 12SW 1256 1356 1456 1556 164/N 16678 RC PYLON RACING SERIES 500 DIA PITCHPRICE 75N 5/N 6I 67/,78 SERIES 400C 9777Io W WIDE BLADE EW EXTRA WIDE N NARROW PROPELLERS TAILORED HELICAL PITCH DEVELOPEDTOGIVE MAXIMUM THRUST AT 4 CYCLE ENGINE RPM ALL THE LATEST TECHNIQUES USED ON OUR PRO SERIES 3 SEE BELOW PITCH THP 66 77 /6 677 6 677 8 67 676 June 1989 157
Edition: Model Aviation - 1989/06
Page Numbers: 36, 37, 38, 39, 157
George M Myers arm 3d HIcksvIlIe NY 11801 ABSTRACT Alaska single- dual-conversion receivers explained ALASKA Talk about response February issue out week re ceived five letters two phone calls Alas kans challenging perceptions Alaska normal week would get couple letters ask ing questions about radios reread February 89 issue page 35 see what said wrong said No trees except coastal Southeast should have said No trees tundra north Brooks Range rest Alaska has plenty trees also got called permafrost state ment have point government maps say can find permafrost under lit erally everything isnt solid rock Only southern rim including Anchorage generally free permafrost Alaska means Great Land People live intensely proud protective Look pile letters Alaska has moun tains rivers forests lakes some fascinating flora fauna found anywhere world Everything about Alaska differ ent has largest number pilots state USA map Alaska overlaid lower 48 Alaska spreads Savannah GA Duluth MN San Diego Heres better look Dave Unruh George has admit really trees Alaskaespecially after Dave Unruh sent TD Coupe up Kenal AK him photo flying site near Kenal AK Spectacular view AMA AVP District Xi Gary R Fuller sent overiay map Aiaska superimposed Lower 48 tip Aieutian Isiands kind gets lost over Nevada Southern California may bit difficult make out coastal islands over Georgia North end South Carolina Tennessee Did really know Alaska large 36 Model Aviation xl VPAnchora9e0 5 r4l&ILVISOMBtAL *15* 5$ * P5*11 2 N ..jN 1000100200200*00 CA thanks Gary R Fuller AMA District XI AVP up Kotzebue sent two pages Alaskan facts overlay map Dave Un ruh Kenai sent pictures answered bunch questions listed 18 flying sites down middle state Ken Howell presi dent Alaska RC Society Anchorage sent description RC flying Alaska fly ing sites Chuck Dimon sent Ketchi kan Rainbird sticker went right SA 16-like Seabird bunch information things see included telephone num bers offers hospitality sort overwhelming metropolitan dweller like letter really blew away came David Lawrence An excerpt follows information last article really got 11 years have lived Alaska have never noticed perma frost dust hills treeless OK now will serious name David Lawrence am 16 years old have hobby four years Im junior local high school has larger population some small cities work hobby store lo cal shopping mall better stocked lot hobby stores West Coast mall con tains 194 stores no sales tax Let give few true facts about city live Anchorage permafrost dust however active logging dustry trees said did exist summer temperature averages about 75 0 F greatnot too hot too cold As driving 100 miles fly could mistaken central loca tion Anchorage can reach nearest fly ing field 15 minutes nearest Slope site 20 minutes good Glider site 20 minutes No matter what bring fly prepared face off against topnotch pilots vid Lawrence 4140 Kutcher Dr Anchorage AK 99516 Keep eye David Lawrence addition letter sent bundle information Alaska including some pictures youll see next month David wants airline pilot think hell good David already knows Continued page 38 Excellent Career Opportunity Model Aviation growing searching experi enced illustrator/draftsman solid RC modeling background whos capable solving design kit-engineering problems An excellent pay benefit package available think youre just person looking send resume Carl Goldberg Models Inc 4734 W Chicago Ave Chicago IL 60651 Department R Carl Goldberg Models Inc An Equal Opportunity Employer Dent Hornswoggled verY IifelinesYo Th6 ushrod5 f aircraftntrol se COntrol re cantsttanycOhorns efltru operatiofl tO JUve can onsidere tro Horra9d kink nail link iocated wi control Robart gall Link CO tob6flflthe yoU th prec Od5 hthe center iout theWit endO after WIlicatirotatin9 ccLJrate what apPbart0fters bail linkoye less bOY5thean additionn expensi ateneed ur horn elimin d Wh waste yo Pushrontrol systems hen ca efficiefl~ timejth RO art mofHorns Ball Link Contro George thinks Power modelers field box might need dandy little tool kit SR Batteries describes column Robart Mfg 1988PO Box 1247 St Charles Illinois 60174 June 1989 37 EA~ SUITABLE FOR ALL MODELS 112A thru GIANT SIZE Wauconda IL 60084 7e9ee / 54$r / 123 1 Cot thin slot hinge 2 Assemble dry 3 Apply tew drops CA glue youre done history modeling few products wore uly revolutionary example proportional radios on-on coverings CA glues permanently chang ed way build fly models thus quality se revolutionary believe EASY HINGES will have same type impact hobby EASY INGES easy install theyre guaranteed ring smile face first time use 5H710 Pkg 24 $255 MFG CO INCMontezuma IA 50171 VjorldS best 5lliflg Chasm eyran Odnds T&G Mfg uul AM Aircraft Sqiply far its outstuuhg rullalilllty Complete single cyl nder system nc ud ng throttlecoupled spark advance kit spa k spark plug lead25 plug battery pack charger 9O shaded 0 Much kmger inimm Easy haid starts no kickback 1INNI-121N10 RPM reidile 0% power toe suckers om kusteht aviubto Lower piced tush no nitro needed d uk pham teed mat 906 pIng cover FermyenpiesUltp2&4stroke sbagleuultwkacybdsrs zoiprmhactsavddilo 0 Spu* calls spu* phgs slielded plum lead & lha*g kits svaIs some Alaskans say nice thing about Anchorage can drive Alaska Ill try visit everyone especially David al though Kotzebue may Out vans range ways get Anchorage Kotze bue over 1000 miles airplane behind dog team boat water soft Kotzebue 1985 population 2633 near Arctic Circle Bering Sea coast Ive recently read 30 books Alaska including James Micheners Alaska have time read book Alaska recommend Adventuring Alaska Peggy Wayburn Sierra Club book ISBN 087156-787-3 paperback Whats difference between single- double-conversion receivers discussing question Mid-Hudson RC Society used sketch seemed help make dif ference clear Ill share RC channels now nominal 10 kHz wide have Fifty RC channels alter nate 50 PRS channels 1000 kHz 72 MHz 73 MHz spacing between signed channel frequencies 1000 10 kHz Thats easy enough understand isnt Now real world both can move about halfway out assigned frequency z want avoid mutual interference Actually want leave little room error move out less 5 kHz So someone asks what differ ence between wideband narrow-band RC ra dio can tell old wideband channels 20 kHz wide new narrowband channels 10 kHz wide Its really simple Transmitters TX send out radio-frequency en ergy receivers RX take Both TX RX contain crystals control frequen cies transmission reception respectively Its done because cheap reliable way have frequency accuracy Because channels close together frequency RX needs trick separate trick called superheterodyning convenience lets talk about system RC38 72550 MHz TX signal mod ulated control information RX crystal part circuit called Lo cal Oscillator LO tuned 72550 MHz Instead can either 455 MHz above below transmitter have singleconversion 455 kHz IF RX call 5C455 IF stands intermediate frequency sake example chose put LO low TX frequency LO puts out un modulated signal 72550 72095 MHz RX antenna picks up modulated 72550 signal TX signal mixed inside RX unmodulated 72095 gen erated LO sum two 144645 difference between 455 MHz Both new signals carry modula tion control information four signals presented intermediate fre quency amplifier IF has properties long wall terms frequency has narrow gate 455 MHz wall blocks other three signals passes modulated signal 455 MHz no 0003fleSa 10 450ranetna radnas 005005 00 IOa nl,c na 00. sketch scale does have 38 Model Aviation Holds twelve gb-plugs Made tough fuel resistant Protects elements ans m hard knocks Keeps gb-plugs neat organized easy find easy use See favorite Hobby Shop Du-Bro Products Inc Bonner Road old wideband 20-kHz-wide gate make point can see signals will pass through gate modulated 455 difference between LO TX signal way want Now look possibilities 1991 Some body comes air RCl5 0 MHz differently modulated signal example receiver takes signal also mixes before mixtures RC38 minus RCl5 concerns us difference 72550 0 doubly modulated once trans mitter Note process RCl5 trans mitter 72090 acts like LO 72095 worst part result fits through old 20-kHz gate very nicely illustrates 21M 23-channel problem wideband SC45Ss RC38 minus RClS hannels 6044-10I 10mc 5046 440ThOU ThISA H55- 80~ 445ASS 20k4040l both modulated signals passed through IF amp decoded presented servo servo confused mixture modulations have interference becomes problem some wideband SC455 RX RCl5 TX few feet closer airplane RC38 TX test RCL5 signal 2 dBM 5 dBM RC38 signal possible build narrow-band SC455 re ceiver can see gate will have narrower z order exclude unwanted signal 460 MHz another way deal prob lem can move gate dual-conversion receiver does mak ing first conversion gate occur 10700 MHz As can see 23-channel problem disappears Using different LO has separated unwanted mixture signal 510 MHz stead 005 MHz before fact closest unwanted signal now PRS385 72560 MHz Mix LO modulated signal occurs frequency 72560 0 10710 MHz Assuming gate width Hz before gets through first gate look what happens gets sec ond gate second local oscillator operating 11155 MHz puts unwanted signal outside second gate NOW 10 kHz-wide narrow-band gate 6044 6046 4 6065 10POSSIS 1010 601$ 00500l07O i4Ok444d44Sd0l 44810 450 J~ fact can now go back first exam ple put closest adjacent channels PRS 375 385 discover TWO MORE modulated signals going through old wideband 20-kHz gate 445 465 MHz make interference servos didnt show single-conversion exam ple because didnt want confuse discus sion narrow-band dual-conversion receiver re Continued page 157 7YAfG MFG Tigerskin~ WHAT DO YOU CALL THE BEST SHEETING MATERIAL FOR FOAM WING CORES Wing Mfg pioneered foam core wing construction early 60s have used everything tangowood 002 stainless steel sheeting last few years have using pressure laminates evolved R & 0 work Uncle Sam Tigerakins pre-finish high density posterboard material clear laminated plastic film top simply apply contact cement such Styro-Stick adhesive cores sheeting press sheeting onto cores material pliable can easily wrap around leading edges Tigerskins CHECK THESE FEATURES Superior strength weight ratio Superior bond capability foam 001 per sq temperature stability Smooth high gloss finish Superior resistance nitro fuel Superior resistance weather Easy apply Low low cost 01/64 x 23 35 size 1*o 0417 Comes following colors Waco Red Polar White Insignia Blue Sun Yellow $495 PER SHEET RING Send check money order required amount Add $395 shipping 1 6 sheets Add $749 shipping 7 12 sheets SEND TO Wing Mfg PO Box 33 Crystal Lake IL 60014 Illinois Residents add 6 1 /251o sales tax ijI Super Styra-Stick wing skin adhesive $596 16 oz Can Item #601 can does wing up 70 No extra shipping cost ordered Tigerekins See Tigerskens Chicago Model & Hobby Show Booth 1735 SEND $350 FOR CATALOG June 1989 39 Invisible SvitchTM direct replacement radio on/off switch Und Ve Call Der Svitch"5 Der Svitch80 on-board magnetic on/oft switch radio equipment hides inside fuselage activated outside included small bar magnet shown above cut awful holes fuselage. Isnt time made Der Svitcb Ideal Any A/C Plane Boat Car Scale Proiects Wafer Flyers Safe use Consumes no power ation free h resistant atible radio Optional red LED lamp installs plane dash wing indicate radio state Simple Install Futaba Airtronics radios order Model 1402 simply unplug on/off switch plug Der Svitch order Model 1401 use connectors old on/ott switch instructions supplied Der Svitch includes bar magnet activator shown above ModelDescnptionPrice ea 1401Der Svitch activator no connectors twisted leads$1995 1401 LEDDer Svitch activator no connectors twisted leads option leads tor external LED #1405$2495 es 1402*Der Svitch activator connectors tor Futaba Airtronics$2495 es 14O2LEDDer Syitch activator connectors tor Fstaba Airtronics option leads tor esternal LED #1405$2995 ea 1405LEO red lawp w124 twisted leads Models 1401 LED 1402LE0$595 * ordering Model 1402 1402LE0 please specify radio connectortypes Connectors available Futaba J Futaba G Airtronics radios order include name address specify models needed include check money order send Ragan/BarkerGroup 5050 Duorum Drive Suite 741 Dallas Texas 75240 Please add $250 per order cover UPS charges Texas residents add sales tax Credit Card orders call between 9 00 500 Central Time M-F Please allow 2-4 weeks delivery Patent Pending Dealer Inquiries Invited F ininin C/L New R/C HANGAR rn CATALOG IKits OR Plans Innovative Inexpensive Quick&Easy Build HORNET 074 Order yours today QUICK & LIVELY SPORT BIPLARE GREAT FOR SMALL FSELIlS Designed new Cnn 074 Queen See enganel SEND 2 Spenificatinona Wing Spurn 2h Oang Area 275 Sq Length 25 Loading 13 SzSq Pt Weoght 1112 Lb Radio iChannel micro servos Experience aileron trainer qoalofoes yoo tn pilot sleek nk inn airplane Sisple dorahie rentangular 2spar hd noons sheeted box type 0 oselage solid tail surfaces pretot aAA balsa ply tollsize illostrated plana STANGEL ENTERPRISES ostb tooplete instroc non ha dna e pa baghtP 0 BC 36 M MEMBER0 AC LPlunn S4995 01350 ShlI Plan ySSe 95 $150 SSHWAUKESHA WSCONON5 bAMJ tively uncommon sizes /32 hard alu minum sheet landing gear stock small 00-90 0-80 hex screws nuts small 00 1 2 wood screws practi cally everything else available hobby shop worry can ordered National Trea sure Scratch Builders Sig Manufactur ing Company Youll also need small nut-drivers screwdrivers use 21-piece tool set sold Polks Model Craft Hobbies Micro-Mark shown ads fine little tools Scale model builders very reasonable price Whether sound Longsters model four-cycle engine conjures memories favorite full-size airplanes have known flownor merely sounds like model four-cycle enginewith its steady flying habits hybrid lightplane/antique sure please Just remem ber winds blow Longster better go Radio Technique/Myers Continued page 39 jects 23-channel problem AND two adjacent-channel problems exist wideband 5C455 receiver Thats Bob Aberle chose identify dual-conversion narrow-band receiver 1991 receiver Note above refers AM FM Theres no difference between far interference type concerned Larry Sribnick has done again Larry friend firm SR Batteries Inc Box 287 Bellport NY 11713 phone 516/2860079 FAX 516/286-0901 now marketing tool kit consists screwdriver-type han dle ratchet handle assortment /a-in hex-shaft tool bits will also fit electric screwdriver whole shebang comes snaplocked bright yellow plastic case sells $2695 plus $3 shipping handling tool bits fit No 1 2 Phillips-head screws /l6 slotted screws 12 sizes English hex keys 050 through 5/lb six sizes metric hex keys 15mm through 5mm adapter Ia-in square-drive sockets components hardened blackened resist rust except ratchet handle stainless steel screw driver handle plastic tool bits have spring-loaded balls lock place An added setscrew socket screwdriver handle insures wont losing tool bits inside model per feet item tool kit can handle things like wheel collars engine mount bolts etc got set immdediately filed two tabs off screwdriver shaft can slip ratchet handle thereon case need give lit tle extra urge stuck screws Should happen damage tool bit replacements available $1 SR Batteries RC Battle/Good Continued page 45 approved five new 72 MHz channels close 3-to-2 decision two Commission ers absent disconcerting dissenting Commissioners opined RC pears essentially triv ial use does warrant allocation spectrum space Caustic words hairbreadth voting coupled disparaging minority opinion might have undercut optimism about course future battles FCC except Courtneys shrewd analysis counsel explained Commissioners votes di vided sharply according respective years service three favor AMA proposal served 12 15 21 years respectively two voted against three years respective tenure caution ary experience Courtneys view confirmed importance continu ally educating public officials about RC hobby would well heed re minder RC Old-Timers/Mathews Continued page 49 original ignition wiring remained consisted mid-Thirties-type automotive acces sory wire totally deteriorated insulation cracked touch re placed unique double-pole double-throw knife-blade switch disassembled cleaned corrosion buffed installed although its used its original location Although laminated balsa wheels re moved sanded tire area repainted THE LEADER IN COMPETITION NEW 4[L#L SERIES 100 THP DESIGN \ /DIAPRICE 15 16 NEW PRO SERIES 3 \ / i S NEW NIGH TECH AIRFOIL SECTION 10T0200/oINCREASE IN THRUST MFG OF SELECT HARD MAPLE WOOD WILL NOT FATIGUE LIKE SYNTHETICS FUELPROOFHIGH LUSTER FINISH DIAPITCH PRICE 534 634 72633456 6334568 645667 9456677/ 104566A7 106W6W 106EW 114677 7 7 46 ii5W ii6EW 1167 124W 12SW 1256 1356 1456 1556 164/N 16678 RC PYLON RACING SERIES 500 DIA PITCHPRICE 75N 5/N 6I 67/,78 SERIES 400C 9777Io W WIDE BLADE EW EXTRA WIDE N NARROW PROPELLERS TAILORED HELICAL PITCH DEVELOPEDTOGIVE MAXIMUM THRUST AT 4 CYCLE ENGINE RPM ALL THE LATEST TECHNIQUES USED ON OUR PRO SERIES 3 SEE BELOW PITCH THP 66 77 /6 677 6 677 8 67 676 June 1989 157