George M Mye Radio Thchnque 70 FmeIUd Fm Rd HIcksvllle NY 1801 ABSTRACT Reader letters intimate Ni-Cd de tails capacity formulas Caring Ni-Cd batter [ies Part 6Ni-Cd peculiarities FIRST letters 1 Walter H Rady Newport NH writes Dear GeorgeI am just getting started elec tric flight rging batteries properly single important thing con fused about articles have spelled out requirements very understandable way charger timer cutoff bat teries overcharged times result ant decrease capacity evident over months flew model already know what happens charger fails sends AC through batteries night left seven stainless steel tubes fuselage full white stuff class want compete doesnt allow battery charging during contest will charging overnight Cl 10 rate ques tion Can put pot leads Polks Multi-Charge-A-Matic charging cur rent can cut 90 mA will voltage drop detector still function Dear Walt Due Ni-Cd cell chemistry voltage drop detector VDD works fast charger could reduce cur rent built-in timer would keep interrupting charge no need VDD overnight charger complicate things would practical use some thing like Ace K/C DMVC purpose DMVC can powered 110 VAC 12 VDC will charge two packs up 10 cells independently rate select up 250 mA contains meter can set current accurately Part No 34K32C $5495 Ace K/C Inc PO Box SuE Higgins ville MO 64037 will find much information need Bob Kopskis K/C Electrics column will found few pages further 2 Now Tom McCowen Valley Ea gles RC Club Anchorage AK 99752 flyaway during Forty BelowThis Must Fun Fly January Everything seemed normal got plane back What can tell about effects low temperature Ni Cds Dear Tom Ni-Cd will deliver 100% ca pacity room temperature failing off higher lower temperatures Available charge drops TE off about one-half percent degree F below freezing data stops 40% loss -20F Half total loss occurs between 00 -20F can see subzero battery temper atures good Camera people work low temperatures keep batteries inside pocket between uses Before blaming batteries Id want see transmitter receiver stay aligned low temperatures Id also want see stiff servos hinges etc become low tem peratures 3 next ones Mike Tobin APO NY Dear George Ni-Cds deteriorate left discharged particular must charge new batteries buy can leave package Dear Mike Discharged Ni-Cds deteri orate stored room temperature main concern will accept full charge first time charged cant make up pack last minute expect much Ni-Cds must go through something like five charge/discharge cycles before can hold full charge first five charges should done overnight rate process takes time 34 Model Aviation 4 next question will long can Ni-Cd batteries stored Nobody knows sure answer depends strongly batteries used stored cells get old enough plate separator material deteriorates electro lyte evaporates may take 10 years idle storage cant inspect separator deterioration does show up loss capac ity Battery cyclers measure charge capacity put paper label pack test spring write test results date sticker see capacity has dropped significant amount cycle pack few times wont come back least 90% rat ing wont fly Other people may recommend battery replace ment 50% 80% rated capacity less may good number flashlight electric screwdriver evaluation considers risk have replace $25 battery pack three years have full capacity operate radio $1000 model will replace Just record dont clalm expert Electric flight nickle-cadmium batteries chargers So get information have aeronautical engineering degree enough additional study qualify degree electrical engineering have flown RC models 30 years time have studied bat tery manuals have tested various types chargers batteries Ive owned maintained couple electric cars boats including some reworking re winding motors Larry Sribnick has friend since started SR business flying buddy Bob Aberle has designed reviewed few Electric models took some data solved some problems During visits couple KRC Electric Fly-Ins amazed performances turned Dr Keith Shaw Bob Kopski others collected information Fast charg ers VDD timer cutoff seem norm have visited RC car tracks carpet rac ers run have observed winning driv ers spend much time testing cells malting socalled balanced packs Balanced packs assem bled cells exhibit similar characteris tics respect superior charge capacity discharge curve under tests Some drivers have computer-controlled test equipment buy batteries gross lots can pick out cells high side production tolerances makes sense have lot work before have battery ready race can buy balanced packs people supply carpet racers about twice price production-run packs pay additional testing SR packs Carpet race drivers use sophisticated fast charg ers VDD timer cutoff cooling fans blow packs being charged manuals say Ni-Cd batteries accept charge room temperature both higher lower temperatures reduce charge ac ceptance manuals also say heating cells charging bad Some hightech fast chargers use temperature sensor bur ied pack cut off fast charging whenever cell temperature rises fixed amount such 5 0C example RCA Hitachi portable VCR includes such charger Some carpet race drivers short exhausted Continued page 36 September 1990 35 RV-3 Deluxe Kit Need Only Join Wing Halves Install Tail Feathers Cover complete Hardware Package Included 88 wingspan G-38 G-62 engine sizes 17-20 lbs weight range information call write PO Box 299 Gonzales Texas 78629 512 672-7023 A\uthorized Ddio CntroI eivice Kraft West Coast Service Center Ohio 4I S SUPER CANOPY Giant 99 x 16 vinyl clad nylon canopy Red ow Blue e Color combo 95uauPm 1-3/8 rugged pipe frame 10 easy out steel tent stakes nylon guys Folds neat heavy duty cardboard box goes up quickly complete instructions Optional name city state printed ends 0 order canopy request additional information call write OHIO SUPERSTAR PRODUCTS Inc 216-223-1950 11376 Ridgeway Road Kensington ohio 44427 SQUARE CUT Tools __ 4073 254-0516 905 N Harbor C ty Blvd Melbourne FL 32935 Dealer/DIUlbuter Inqultius InvIted F da Pea data Add 6% Sales Ta, 36 Model Aviation packs resistive load store shorting resistor battery bug place battery bug assembly LED di ode resistors takes pack down about volt Either item supposed keep packs balanced None battery manufac turers agree procedure heres may have noticed cell discharge curves never go zero volts reason Any battery makes electricity chemistry stick penny nickle lemon will see voltage between coins Thats chem istry manufacturer assembles compo nents battery like sticking coins lemon voltage will appear between termi nals cell before charged voltage 06 VDC will continue long battery usable leave Ni-Cd battery shelf 10 years good cells will still read 06 09 VDC charge because chemistry chemistry helps hold electrolyte place Shorting cell 0 volts bad because pro motes creep leakage electrolyte out cell According Red Scholefield Gates En ergy Products manufacturers short out cells short-down/spring-back test weeds out weak cells short cell indi vidually 0 volts 24 hours re move short measure voltage cell doesnt spring back least 06 volts bad cell must discarded manuals say completely discharging pack time use cuts usable number charge/discharge cycles little one-third number cycles obtainable batter ies partially discharged before recharg ing want win car races thing want batteries last another Ive noticed situation kinds competition tests have shown battery tests use less unless duplicate end-use conditions example hobby cycler/charger will discharge battery drawing some amperage between 2C C/2 will cut off 11 09 volts per cell again respecting cell chemistry get number battety charge capacity useful transmitters receivers means absolutely nothing use same battery electric propulsion same test 10 amps endpoint volt per cell will measure smaller capacity manuals say apparent loss capac ity high discharge rates evidence cell de sign chemistry also say full ca pacity still can get out lower discharge rates have observed cell voltage rises rapidly after remove load produces heavy current drain supports view Battery construction makes difference use Sanyo cells orange red label high-current test will yield greater percentage rated capacity same test performed yellow-label cell other hand measure capacity af ter charged cell has storage month yellow-label cell may show 90% red-label cell shows 50% Thats labels have different colors doesnt end cells Using wrong plugs wires can reduce power delivered motor one-third So can overheating cell sol dering wire Continued page 150 WHEN YOU FORGET\OUR UNITS REMEMBER RC System NICd Batteries MI chargers need- padcagel Cycler-Charger *23996 Fits 48V Ra 96V Tx packsPlus $5 S&H Others available write call IRegular Model.. $4696 ForPlus $3 S&H11 ld kit sinaiPlus $3 S&H electric boat batteriesSpecIfy 612 24V Heavy Duty Model*6896 sport winch large boat andPlus $4 S&H electric power charging battenesSpecify 6 1 2V CaRa ProductsSASEIorS*tmaiionPO Box 221 605-9875924Dealersliwlied canton SD 57013 wnetner Ku OUIIUS[ suraiuii US SQUARE CUT Tools will save time Remove stubborn die cuts cut own squares slots Made US quality machined nickel plated steel Order set today See Daler Cataloger Order dont carry Sqsare cut Tools call us call well pay shipping US canada COD txtral ~~1~~I 209 645 5535 GOLDEN GATE HOBBIES PO BOX 27001 FRESNO CAUFORNIA 93729 M/CVISA OR COD HA TORI RA DICICON IMMSK HATORI BLUEPRINT SHOWS ALL EXHAUST ITEMS FULL SIZE 2FF X 4FT $ 5 WE WANT NEW DEALERS ! HATORI 650 LONG PIPE $4350 TO DEALERS CATALOG $ 200 OR FREE Will-I ORDERS Mere Fun less Funds ving pan62/2 inches Wing Area770 square inches Engine Size 10 cc 90 120 four stroke Designed AMA FAI Turn-around pattern Foam wing stab 3-32 Balsa sheet covering Tricycle conven lional gear fixed retracts Rear side exhaust fiber glass canopy Very positive maneuverable XLT SPECIFICA Wing Span65 inches Length65 inches Wing Area845 square inches Recommended Engine Size 10 cc 90 120 four stroke XLT designed tuned pipe re tract landing gears Capable AMA Turn-around pattern Rear side ex haust SPECIFICATIONS Wing Span Wing Area Engine Size 63Y4 inches 700 square inches 50-60 Glow 90 four stroke fun sport pattern turn-around can done Utter Chaos completely built up Balsa construction Canopy engine mount included years proven flying reliablity BRIDI AIRCRAFT DESIGNS INC 23625 Pineforest Lane Harbor City California 90710 213 549-8264 213 326-5013 SEE YOUR FAVORITE HOBBY SHOP OR RETAIL OUTLETW Dealer Inqurles Invited D&J ELECTRONICS 900 Lucy Road ll Ml 48843 546-2644 service makes RIO equipment utilizing state art electronics Spectrum Analyzer Precision Frequency Measuring equipment True 1991 Standards endorsed AMA & ROMA Transmitter Slicker Program FCC LicensedSpeed Central RepairsQuality Service Transmitter Checks Only includes GOLD/SILVER slicker$400 Transmitter & Receiver Calibration$2400 Frequency Upgrades & Changes crystals extra$2900 Bench Time Repairs per hour$2500 Transmitters service will receive AMA/RCMA sticker ADD $500 FOR SHIPPING & INSURANCE TURN AROUND TIME TWO WEEKS OR LESSIi UPSLJ ISA/MASTERCARD ACCEPTEDCOD Pea Patch/Shepherd Continued page 32 used form shape cowl Cut block inside dimensions sections AA B-B Epoxy B-B pattern side draw alignment lines foam properly position A-A pattern Glue A-A place shown picture Glue foam nose block A-A use 80- 100-grit sandpaper shape foam around patterns youre satisfied shape lay fiberglass cloth ever foam securing five-minute epoxy achieve snugness final one-hour epoxy used Youll need cut darts cloth good fit over form Try keep smooth possible avoid ex cessive sanding after epoxy applied Mix up batch Sig one-hour epoxy let soak fiberglass cloth using throwaway brush heat lamp hair dryer will speed up epoxy cure first coat dry knock off bumps rough spots coarse paper mix up apply second coat epoxy Sand 180-grit paper dry Use Sig glass beads epoxy Epoxilite have some handy fill low spots part smoothed satis faction cut away B-B hog out foam screwdriver Cut away A-A us ing Dremel-type tool router sand ing drum Glue F-lA front firewall along small hardwood blocks trial fit cowl trimming get flush fit fuselage sheeting Install en gine begin cutting away cowl fit over fit accurate screw cowl place Cut 2-in ring Lite Ply epoxy front cowl its centered engine shaft Glue rear block over stab sand shape Assemble tail wheel fittings epoxy tail wheel slot tail post Cevering finishing fuselage fin rudder covered Sig Koverall using nitrate dope wing stab/ele vator covered plastic film Dope brushed framework whereve covering contacted wood Stretc covering over fuselage th grain running crosswise lengthwise apply dope through covering t contact wood After tightening heat iron fabric given three coat nitrate clear Red Devil polyurethane almon shade gives original its cream cobs paint also sprayed th film holding up very well after mar flights black pinstriping A-i size Coverste Vinyl stick-on letterir office supply store used Pasture Pilots PPA logo t strictly tongue-in-cheek addition brought smile two seems amuse others notice logo w made Coverite Graphic Sheet thi painted old-timer cockpit ma Williams Bros 2%-in Sportsman simulate 1920s-style cap dabb baking soda small brush ad ed thin CyA repeating process until artful facsimile made bri piece A2 ply glued ti back cap rubberband used f elastic goggles After pinning windscreen place traced around its front ball-point pe carefully cut away covering #11 X-Acto knife leaving approximately /32 groove wood glued en Testors clear household c ment aluminum flange win screen made two strips Coven tape Which painted silver Frem initial inspiratien dna ing building stages finally relis ing its talents flier Ive received ma hours pleasure airplane Its realistic-looking model carries ne ism sky thats way enjo ing RC Pea Patch should satisfy Ha py touch-and-goes Radio Technique/Myers Continued page 36 can estimate current drawn ek tric motor dividing measured battery cap 150 Model Aviation ity time ran assuming run un dl power drops off unusable level example have 800-mAh battery motor runs six minutes average cur rent about 006 x mAli/minutes Average current 006 x 800 mAh/6 mm ps estimated 06 multiplier contains 60 minutes/ hour divided 1000 milliamps/amp make units come out right reasonable estimate because motor current almost constant thats due flat voltage/time discharge characteristic good Ni-Cd batteries can rearrange formula estimate bat tery capacity way acts service measure motor current ground see average about 10 amps find pack lasts five minutes air use ful capacity about amps x minutes/006 10 amps x 5 min/06 mAh no matter what label battery says can apply above formula radio bat teries 500-mAh pack flew plane two hours average current drawn 006 x 500 mAh/120 mm amps considering radio system service should keep mind oniy transmitter cur rent constant receiver current varies minimum current servos quiet about 10 amp maximum current sev eral servos working hard can sev eral amps depends number type servos connected receiver ihey used above learn make few con trol inputs necessary after low battery voltage detector tells batteries have discharged warning point less current demand likely have enough land formulas correct regardless number cells battery set up Airtronics Vision 8 Sail plane transmitter complex process friend John Clarke has spent much time learning spent time making videotape showing process step step separate illustrate process John has cluded some great Sailplane videos Order tape John F Clarke 911 Cov ert Ave New Hyde Park NY 11040 price $1995 plus $350 P&H New York residents add sales tax Narrow Banding/Smith Continued page 37 concentrate really practical equip ment five excellent Guidelinecertified FM radios available under $220 Six-channel models two brands commonly sold under $170 both outstanding high-quality val ues Now time fret about chang ing horses midstream brandwise Youll starting fresh some degree would probably good idea think twice about empowering collection old servos dictate new-equipment selec tions us careful approach narrow-banding can present serious sticker shock Establish plan begin im plement new-equipment purchase way youll get encourag ing taste flying least plane new rig experience will help keep narrow-banding program track Re-equipping pain theres no ques tion about concentrate what youll gain rather what youll giv ing up perhaps youll feel cheerful about abandoning much less-worthy gear Actually figure what renewed equipment will deliver length service factor security dandy new stuff can impart might come conclusion price youll pay could best RC investment youve ever made Its investment will come added payoff knowing youll well de fended battle frequencies Nineties may experience warm feeling about sacrifice will benefit fellow RCers Okay okayjust pretend didnt make last comment responding advertisers mention read about Model Aviation September 1990 151
Edition: Model Aviation - 1990/09
Page Numbers: 34, 35, 36, 150, 151
George M Mye Radio Thchnque 70 FmeIUd Fm Rd HIcksvllle NY 1801 ABSTRACT Reader letters intimate Ni-Cd de tails capacity formulas Caring Ni-Cd batter [ies Part 6Ni-Cd peculiarities FIRST letters 1 Walter H Rady Newport NH writes Dear GeorgeI am just getting started elec tric flight rging batteries properly single important thing con fused about articles have spelled out requirements very understandable way charger timer cutoff bat teries overcharged times result ant decrease capacity evident over months flew model already know what happens charger fails sends AC through batteries night left seven stainless steel tubes fuselage full white stuff class want compete doesnt allow battery charging during contest will charging overnight Cl 10 rate ques tion Can put pot leads Polks Multi-Charge-A-Matic charging cur rent can cut 90 mA will voltage drop detector still function Dear Walt Due Ni-Cd cell chemistry voltage drop detector VDD works fast charger could reduce cur rent built-in timer would keep interrupting charge no need VDD overnight charger complicate things would practical use some thing like Ace K/C DMVC purpose DMVC can powered 110 VAC 12 VDC will charge two packs up 10 cells independently rate select up 250 mA contains meter can set current accurately Part No 34K32C $5495 Ace K/C Inc PO Box SuE Higgins ville MO 64037 will find much information need Bob Kopskis K/C Electrics column will found few pages further 2 Now Tom McCowen Valley Ea gles RC Club Anchorage AK 99752 flyaway during Forty BelowThis Must Fun Fly January Everything seemed normal got plane back What can tell about effects low temperature Ni Cds Dear Tom Ni-Cd will deliver 100% ca pacity room temperature failing off higher lower temperatures Available charge drops TE off about one-half percent degree F below freezing data stops 40% loss -20F Half total loss occurs between 00 -20F can see subzero battery temper atures good Camera people work low temperatures keep batteries inside pocket between uses Before blaming batteries Id want see transmitter receiver stay aligned low temperatures Id also want see stiff servos hinges etc become low tem peratures 3 next ones Mike Tobin APO NY Dear George Ni-Cds deteriorate left discharged particular must charge new batteries buy can leave package Dear Mike Discharged Ni-Cds deteri orate stored room temperature main concern will accept full charge first time charged cant make up pack last minute expect much Ni-Cds must go through something like five charge/discharge cycles before can hold full charge first five charges should done overnight rate process takes time 34 Model Aviation 4 next question will long can Ni-Cd batteries stored Nobody knows sure answer depends strongly batteries used stored cells get old enough plate separator material deteriorates electro lyte evaporates may take 10 years idle storage cant inspect separator deterioration does show up loss capac ity Battery cyclers measure charge capacity put paper label pack test spring write test results date sticker see capacity has dropped significant amount cycle pack few times wont come back least 90% rat ing wont fly Other people may recommend battery replace ment 50% 80% rated capacity less may good number flashlight electric screwdriver evaluation considers risk have replace $25 battery pack three years have full capacity operate radio $1000 model will replace Just record dont clalm expert Electric flight nickle-cadmium batteries chargers So get information have aeronautical engineering degree enough additional study qualify degree electrical engineering have flown RC models 30 years time have studied bat tery manuals have tested various types chargers batteries Ive owned maintained couple electric cars boats including some reworking re winding motors Larry Sribnick has friend since started SR business flying buddy Bob Aberle has designed reviewed few Electric models took some data solved some problems During visits couple KRC Electric Fly-Ins amazed performances turned Dr Keith Shaw Bob Kopski others collected information Fast charg ers VDD timer cutoff seem norm have visited RC car tracks carpet rac ers run have observed winning driv ers spend much time testing cells malting socalled balanced packs Balanced packs assem bled cells exhibit similar characteris tics respect superior charge capacity discharge curve under tests Some drivers have computer-controlled test equipment buy batteries gross lots can pick out cells high side production tolerances makes sense have lot work before have battery ready race can buy balanced packs people supply carpet racers about twice price production-run packs pay additional testing SR packs Carpet race drivers use sophisticated fast charg ers VDD timer cutoff cooling fans blow packs being charged manuals say Ni-Cd batteries accept charge room temperature both higher lower temperatures reduce charge ac ceptance manuals also say heating cells charging bad Some hightech fast chargers use temperature sensor bur ied pack cut off fast charging whenever cell temperature rises fixed amount such 5 0C example RCA Hitachi portable VCR includes such charger Some carpet race drivers short exhausted Continued page 36 September 1990 35 RV-3 Deluxe Kit Need Only Join Wing Halves Install Tail Feathers Cover complete Hardware Package Included 88 wingspan G-38 G-62 engine sizes 17-20 lbs weight range information call write PO Box 299 Gonzales Texas 78629 512 672-7023 A\uthorized Ddio CntroI eivice Kraft West Coast Service Center Ohio 4I S SUPER CANOPY Giant 99 x 16 vinyl clad nylon canopy Red ow Blue e Color combo 95uauPm 1-3/8 rugged pipe frame 10 easy out steel tent stakes nylon guys Folds neat heavy duty cardboard box goes up quickly complete instructions Optional name city state printed ends 0 order canopy request additional information call write OHIO SUPERSTAR PRODUCTS Inc 216-223-1950 11376 Ridgeway Road Kensington ohio 44427 SQUARE CUT Tools __ 4073 254-0516 905 N Harbor C ty Blvd Melbourne FL 32935 Dealer/DIUlbuter Inqultius InvIted F da Pea data Add 6% Sales Ta, 36 Model Aviation packs resistive load store shorting resistor battery bug place battery bug assembly LED di ode resistors takes pack down about volt Either item supposed keep packs balanced None battery manufac turers agree procedure heres may have noticed cell discharge curves never go zero volts reason Any battery makes electricity chemistry stick penny nickle lemon will see voltage between coins Thats chem istry manufacturer assembles compo nents battery like sticking coins lemon voltage will appear between termi nals cell before charged voltage 06 VDC will continue long battery usable leave Ni-Cd battery shelf 10 years good cells will still read 06 09 VDC charge because chemistry chemistry helps hold electrolyte place Shorting cell 0 volts bad because pro motes creep leakage electrolyte out cell According Red Scholefield Gates En ergy Products manufacturers short out cells short-down/spring-back test weeds out weak cells short cell indi vidually 0 volts 24 hours re move short measure voltage cell doesnt spring back least 06 volts bad cell must discarded manuals say completely discharging pack time use cuts usable number charge/discharge cycles little one-third number cycles obtainable batter ies partially discharged before recharg ing want win car races thing want batteries last another Ive noticed situation kinds competition tests have shown battery tests use less unless duplicate end-use conditions example hobby cycler/charger will discharge battery drawing some amperage between 2C C/2 will cut off 11 09 volts per cell again respecting cell chemistry get number battety charge capacity useful transmitters receivers means absolutely nothing use same battery electric propulsion same test 10 amps endpoint volt per cell will measure smaller capacity manuals say apparent loss capac ity high discharge rates evidence cell de sign chemistry also say full ca pacity still can get out lower discharge rates have observed cell voltage rises rapidly after remove load produces heavy current drain supports view Battery construction makes difference use Sanyo cells orange red label high-current test will yield greater percentage rated capacity same test performed yellow-label cell other hand measure capacity af ter charged cell has storage month yellow-label cell may show 90% red-label cell shows 50% Thats labels have different colors doesnt end cells Using wrong plugs wires can reduce power delivered motor one-third So can overheating cell sol dering wire Continued page 150 WHEN YOU FORGET\OUR UNITS REMEMBER RC System NICd Batteries MI chargers need- padcagel Cycler-Charger *23996 Fits 48V Ra 96V Tx packsPlus $5 S&H Others available write call IRegular Model.. $4696 ForPlus $3 S&H11 ld kit sinaiPlus $3 S&H electric boat batteriesSpecIfy 612 24V Heavy Duty Model*6896 sport winch large boat andPlus $4 S&H electric power charging battenesSpecify 6 1 2V CaRa ProductsSASEIorS*tmaiionPO Box 221 605-9875924Dealersliwlied canton SD 57013 wnetner Ku OUIIUS[ suraiuii US SQUARE CUT Tools will save time Remove stubborn die cuts cut own squares slots Made US quality machined nickel plated steel Order set today See Daler Cataloger Order dont carry Sqsare cut Tools call us call well pay shipping US canada COD txtral ~~1~~I 209 645 5535 GOLDEN GATE HOBBIES PO BOX 27001 FRESNO CAUFORNIA 93729 M/CVISA OR COD HA TORI RA DICICON IMMSK HATORI BLUEPRINT SHOWS ALL EXHAUST ITEMS FULL SIZE 2FF X 4FT $ 5 WE WANT NEW DEALERS ! HATORI 650 LONG PIPE $4350 TO DEALERS CATALOG $ 200 OR FREE Will-I ORDERS Mere Fun less Funds ving pan62/2 inches Wing Area770 square inches Engine Size 10 cc 90 120 four stroke Designed AMA FAI Turn-around pattern Foam wing stab 3-32 Balsa sheet covering Tricycle conven lional gear fixed retracts Rear side exhaust fiber glass canopy Very positive maneuverable XLT SPECIFICA Wing Span65 inches Length65 inches Wing Area845 square inches Recommended Engine Size 10 cc 90 120 four stroke XLT designed tuned pipe re tract landing gears Capable AMA Turn-around pattern Rear side ex haust SPECIFICATIONS Wing Span Wing Area Engine Size 63Y4 inches 700 square inches 50-60 Glow 90 four stroke fun sport pattern turn-around can done Utter Chaos completely built up Balsa construction Canopy engine mount included years proven flying reliablity BRIDI AIRCRAFT DESIGNS INC 23625 Pineforest Lane Harbor City California 90710 213 549-8264 213 326-5013 SEE YOUR FAVORITE HOBBY SHOP OR RETAIL OUTLETW Dealer Inqurles Invited D&J ELECTRONICS 900 Lucy Road ll Ml 48843 546-2644 service makes RIO equipment utilizing state art electronics Spectrum Analyzer Precision Frequency Measuring equipment True 1991 Standards endorsed AMA & ROMA Transmitter Slicker Program FCC LicensedSpeed Central RepairsQuality Service Transmitter Checks Only includes GOLD/SILVER slicker$400 Transmitter & Receiver Calibration$2400 Frequency Upgrades & Changes crystals extra$2900 Bench Time Repairs per hour$2500 Transmitters service will receive AMA/RCMA sticker ADD $500 FOR SHIPPING & INSURANCE TURN AROUND TIME TWO WEEKS OR LESSIi UPSLJ ISA/MASTERCARD ACCEPTEDCOD Pea Patch/Shepherd Continued page 32 used form shape cowl Cut block inside dimensions sections AA B-B Epoxy B-B pattern side draw alignment lines foam properly position A-A pattern Glue A-A place shown picture Glue foam nose block A-A use 80- 100-grit sandpaper shape foam around patterns youre satisfied shape lay fiberglass cloth ever foam securing five-minute epoxy achieve snugness final one-hour epoxy used Youll need cut darts cloth good fit over form Try keep smooth possible avoid ex cessive sanding after epoxy applied Mix up batch Sig one-hour epoxy let soak fiberglass cloth using throwaway brush heat lamp hair dryer will speed up epoxy cure first coat dry knock off bumps rough spots coarse paper mix up apply second coat epoxy Sand 180-grit paper dry Use Sig glass beads epoxy Epoxilite have some handy fill low spots part smoothed satis faction cut away B-B hog out foam screwdriver Cut away A-A us ing Dremel-type tool router sand ing drum Glue F-lA front firewall along small hardwood blocks trial fit cowl trimming get flush fit fuselage sheeting Install en gine begin cutting away cowl fit over fit accurate screw cowl place Cut 2-in ring Lite Ply epoxy front cowl its centered engine shaft Glue rear block over stab sand shape Assemble tail wheel fittings epoxy tail wheel slot tail post Cevering finishing fuselage fin rudder covered Sig Koverall using nitrate dope wing stab/ele vator covered plastic film Dope brushed framework whereve covering contacted wood Stretc covering over fuselage th grain running crosswise lengthwise apply dope through covering t contact wood After tightening heat iron fabric given three coat nitrate clear Red Devil polyurethane almon shade gives original its cream cobs paint also sprayed th film holding up very well after mar flights black pinstriping A-i size Coverste Vinyl stick-on letterir office supply store used Pasture Pilots PPA logo t strictly tongue-in-cheek addition brought smile two seems amuse others notice logo w made Coverite Graphic Sheet thi painted old-timer cockpit ma Williams Bros 2%-in Sportsman simulate 1920s-style cap dabb baking soda small brush ad ed thin CyA repeating process until artful facsimile made bri piece A2 ply glued ti back cap rubberband used f elastic goggles After pinning windscreen place traced around its front ball-point pe carefully cut away covering #11 X-Acto knife leaving approximately /32 groove wood glued en Testors clear household c ment aluminum flange win screen made two strips Coven tape Which painted silver Frem initial inspiratien dna ing building stages finally relis ing its talents flier Ive received ma hours pleasure airplane Its realistic-looking model carries ne ism sky thats way enjo ing RC Pea Patch should satisfy Ha py touch-and-goes Radio Technique/Myers Continued page 36 can estimate current drawn ek tric motor dividing measured battery cap 150 Model Aviation ity time ran assuming run un dl power drops off unusable level example have 800-mAh battery motor runs six minutes average cur rent about 006 x mAli/minutes Average current 006 x 800 mAh/6 mm ps estimated 06 multiplier contains 60 minutes/ hour divided 1000 milliamps/amp make units come out right reasonable estimate because motor current almost constant thats due flat voltage/time discharge characteristic good Ni-Cd batteries can rearrange formula estimate bat tery capacity way acts service measure motor current ground see average about 10 amps find pack lasts five minutes air use ful capacity about amps x minutes/006 10 amps x 5 min/06 mAh no matter what label battery says can apply above formula radio bat teries 500-mAh pack flew plane two hours average current drawn 006 x 500 mAh/120 mm amps considering radio system service should keep mind oniy transmitter cur rent constant receiver current varies minimum current servos quiet about 10 amp maximum current sev eral servos working hard can sev eral amps depends number type servos connected receiver ihey used above learn make few con trol inputs necessary after low battery voltage detector tells batteries have discharged warning point less current demand likely have enough land formulas correct regardless number cells battery set up Airtronics Vision 8 Sail plane transmitter complex process friend John Clarke has spent much time learning spent time making videotape showing process step step separate illustrate process John has cluded some great Sailplane videos Order tape John F Clarke 911 Cov ert Ave New Hyde Park NY 11040 price $1995 plus $350 P&H New York residents add sales tax Narrow Banding/Smith Continued page 37 concentrate really practical equip ment five excellent Guidelinecertified FM radios available under $220 Six-channel models two brands commonly sold under $170 both outstanding high-quality val ues Now time fret about chang ing horses midstream brandwise Youll starting fresh some degree would probably good idea think twice about empowering collection old servos dictate new-equipment selec tions us careful approach narrow-banding can present serious sticker shock Establish plan begin im plement new-equipment purchase way youll get encourag ing taste flying least plane new rig experience will help keep narrow-banding program track Re-equipping pain theres no ques tion about concentrate what youll gain rather what youll giv ing up perhaps youll feel cheerful about abandoning much less-worthy gear Actually figure what renewed equipment will deliver length service factor security dandy new stuff can impart might come conclusion price youll pay could best RC investment youve ever made Its investment will come added payoff knowing youll well de fended battle frequencies Nineties may experience warm feeling about sacrifice will benefit fellow RCers Okay okayjust pretend didnt make last comment responding advertisers mention read about Model Aviation September 1990 151
Edition: Model Aviation - 1990/09
Page Numbers: 34, 35, 36, 150, 151
George M Mye Radio Thchnque 70 FmeIUd Fm Rd HIcksvllle NY 1801 ABSTRACT Reader letters intimate Ni-Cd de tails capacity formulas Caring Ni-Cd batter [ies Part 6Ni-Cd peculiarities FIRST letters 1 Walter H Rady Newport NH writes Dear GeorgeI am just getting started elec tric flight rging batteries properly single important thing con fused about articles have spelled out requirements very understandable way charger timer cutoff bat teries overcharged times result ant decrease capacity evident over months flew model already know what happens charger fails sends AC through batteries night left seven stainless steel tubes fuselage full white stuff class want compete doesnt allow battery charging during contest will charging overnight Cl 10 rate ques tion Can put pot leads Polks Multi-Charge-A-Matic charging cur rent can cut 90 mA will voltage drop detector still function Dear Walt Due Ni-Cd cell chemistry voltage drop detector VDD works fast charger could reduce cur rent built-in timer would keep interrupting charge no need VDD overnight charger complicate things would practical use some thing like Ace K/C DMVC purpose DMVC can powered 110 VAC 12 VDC will charge two packs up 10 cells independently rate select up 250 mA contains meter can set current accurately Part No 34K32C $5495 Ace K/C Inc PO Box SuE Higgins ville MO 64037 will find much information need Bob Kopskis K/C Electrics column will found few pages further 2 Now Tom McCowen Valley Ea gles RC Club Anchorage AK 99752 flyaway during Forty BelowThis Must Fun Fly January Everything seemed normal got plane back What can tell about effects low temperature Ni Cds Dear Tom Ni-Cd will deliver 100% ca pacity room temperature failing off higher lower temperatures Available charge drops TE off about one-half percent degree F below freezing data stops 40% loss -20F Half total loss occurs between 00 -20F can see subzero battery temper atures good Camera people work low temperatures keep batteries inside pocket between uses Before blaming batteries Id want see transmitter receiver stay aligned low temperatures Id also want see stiff servos hinges etc become low tem peratures 3 next ones Mike Tobin APO NY Dear George Ni-Cds deteriorate left discharged particular must charge new batteries buy can leave package Dear Mike Discharged Ni-Cds deteri orate stored room temperature main concern will accept full charge first time charged cant make up pack last minute expect much Ni-Cds must go through something like five charge/discharge cycles before can hold full charge first five charges should done overnight rate process takes time 34 Model Aviation 4 next question will long can Ni-Cd batteries stored Nobody knows sure answer depends strongly batteries used stored cells get old enough plate separator material deteriorates electro lyte evaporates may take 10 years idle storage cant inspect separator deterioration does show up loss capac ity Battery cyclers measure charge capacity put paper label pack test spring write test results date sticker see capacity has dropped significant amount cycle pack few times wont come back least 90% rat ing wont fly Other people may recommend battery replace ment 50% 80% rated capacity less may good number flashlight electric screwdriver evaluation considers risk have replace $25 battery pack three years have full capacity operate radio $1000 model will replace Just record dont clalm expert Electric flight nickle-cadmium batteries chargers So get information have aeronautical engineering degree enough additional study qualify degree electrical engineering have flown RC models 30 years time have studied bat tery manuals have tested various types chargers batteries Ive owned maintained couple electric cars boats including some reworking re winding motors Larry Sribnick has friend since started SR business flying buddy Bob Aberle has designed reviewed few Electric models took some data solved some problems During visits couple KRC Electric Fly-Ins amazed performances turned Dr Keith Shaw Bob Kopski others collected information Fast charg ers VDD timer cutoff seem norm have visited RC car tracks carpet rac ers run have observed winning driv ers spend much time testing cells malting socalled balanced packs Balanced packs assem bled cells exhibit similar characteris tics respect superior charge capacity discharge curve under tests Some drivers have computer-controlled test equipment buy batteries gross lots can pick out cells high side production tolerances makes sense have lot work before have battery ready race can buy balanced packs people supply carpet racers about twice price production-run packs pay additional testing SR packs Carpet race drivers use sophisticated fast charg ers VDD timer cutoff cooling fans blow packs being charged manuals say Ni-Cd batteries accept charge room temperature both higher lower temperatures reduce charge ac ceptance manuals also say heating cells charging bad Some hightech fast chargers use temperature sensor bur ied pack cut off fast charging whenever cell temperature rises fixed amount such 5 0C example RCA Hitachi portable VCR includes such charger Some carpet race drivers short exhausted Continued page 36 September 1990 35 RV-3 Deluxe Kit Need Only Join Wing Halves Install Tail Feathers Cover complete Hardware Package Included 88 wingspan G-38 G-62 engine sizes 17-20 lbs weight range information call write PO Box 299 Gonzales Texas 78629 512 672-7023 A\uthorized Ddio CntroI eivice Kraft West Coast Service Center Ohio 4I S SUPER CANOPY Giant 99 x 16 vinyl clad nylon canopy Red ow Blue e Color combo 95uauPm 1-3/8 rugged pipe frame 10 easy out steel tent stakes nylon guys Folds neat heavy duty cardboard box goes up quickly complete instructions Optional name city state printed ends 0 order canopy request additional information call write OHIO SUPERSTAR PRODUCTS Inc 216-223-1950 11376 Ridgeway Road Kensington ohio 44427 SQUARE CUT Tools __ 4073 254-0516 905 N Harbor C ty Blvd Melbourne FL 32935 Dealer/DIUlbuter Inqultius InvIted F da Pea data Add 6% Sales Ta, 36 Model Aviation packs resistive load store shorting resistor battery bug place battery bug assembly LED di ode resistors takes pack down about volt Either item supposed keep packs balanced None battery manufac turers agree procedure heres may have noticed cell discharge curves never go zero volts reason Any battery makes electricity chemistry stick penny nickle lemon will see voltage between coins Thats chem istry manufacturer assembles compo nents battery like sticking coins lemon voltage will appear between termi nals cell before charged voltage 06 VDC will continue long battery usable leave Ni-Cd battery shelf 10 years good cells will still read 06 09 VDC charge because chemistry chemistry helps hold electrolyte place Shorting cell 0 volts bad because pro motes creep leakage electrolyte out cell According Red Scholefield Gates En ergy Products manufacturers short out cells short-down/spring-back test weeds out weak cells short cell indi vidually 0 volts 24 hours re move short measure voltage cell doesnt spring back least 06 volts bad cell must discarded manuals say completely discharging pack time use cuts usable number charge/discharge cycles little one-third number cycles obtainable batter ies partially discharged before recharg ing want win car races thing want batteries last another Ive noticed situation kinds competition tests have shown battery tests use less unless duplicate end-use conditions example hobby cycler/charger will discharge battery drawing some amperage between 2C C/2 will cut off 11 09 volts per cell again respecting cell chemistry get number battety charge capacity useful transmitters receivers means absolutely nothing use same battery electric propulsion same test 10 amps endpoint volt per cell will measure smaller capacity manuals say apparent loss capac ity high discharge rates evidence cell de sign chemistry also say full ca pacity still can get out lower discharge rates have observed cell voltage rises rapidly after remove load produces heavy current drain supports view Battery construction makes difference use Sanyo cells orange red label high-current test will yield greater percentage rated capacity same test performed yellow-label cell other hand measure capacity af ter charged cell has storage month yellow-label cell may show 90% red-label cell shows 50% Thats labels have different colors doesnt end cells Using wrong plugs wires can reduce power delivered motor one-third So can overheating cell sol dering wire Continued page 150 WHEN YOU FORGET\OUR UNITS REMEMBER RC System NICd Batteries MI chargers need- padcagel Cycler-Charger *23996 Fits 48V Ra 96V Tx packsPlus $5 S&H Others available write call IRegular Model.. $4696 ForPlus $3 S&H11 ld kit sinaiPlus $3 S&H electric boat batteriesSpecIfy 612 24V Heavy Duty Model*6896 sport winch large boat andPlus $4 S&H electric power charging battenesSpecify 6 1 2V CaRa ProductsSASEIorS*tmaiionPO Box 221 605-9875924Dealersliwlied canton SD 57013 wnetner Ku OUIIUS[ suraiuii US SQUARE CUT Tools will save time Remove stubborn die cuts cut own squares slots Made US quality machined nickel plated steel Order set today See Daler Cataloger Order dont carry Sqsare cut Tools call us call well pay shipping US canada COD txtral ~~1~~I 209 645 5535 GOLDEN GATE HOBBIES PO BOX 27001 FRESNO CAUFORNIA 93729 M/CVISA OR COD HA TORI RA DICICON IMMSK HATORI BLUEPRINT SHOWS ALL EXHAUST ITEMS FULL SIZE 2FF X 4FT $ 5 WE WANT NEW DEALERS ! HATORI 650 LONG PIPE $4350 TO DEALERS CATALOG $ 200 OR FREE Will-I ORDERS Mere Fun less Funds ving pan62/2 inches Wing Area770 square inches Engine Size 10 cc 90 120 four stroke Designed AMA FAI Turn-around pattern Foam wing stab 3-32 Balsa sheet covering Tricycle conven lional gear fixed retracts Rear side exhaust fiber glass canopy Very positive maneuverable XLT SPECIFICA Wing Span65 inches Length65 inches Wing Area845 square inches Recommended Engine Size 10 cc 90 120 four stroke XLT designed tuned pipe re tract landing gears Capable AMA Turn-around pattern Rear side ex haust SPECIFICATIONS Wing Span Wing Area Engine Size 63Y4 inches 700 square inches 50-60 Glow 90 four stroke fun sport pattern turn-around can done Utter Chaos completely built up Balsa construction Canopy engine mount included years proven flying reliablity BRIDI AIRCRAFT DESIGNS INC 23625 Pineforest Lane Harbor City California 90710 213 549-8264 213 326-5013 SEE YOUR FAVORITE HOBBY SHOP OR RETAIL OUTLETW Dealer Inqurles Invited D&J ELECTRONICS 900 Lucy Road ll Ml 48843 546-2644 service makes RIO equipment utilizing state art electronics Spectrum Analyzer Precision Frequency Measuring equipment True 1991 Standards endorsed AMA & ROMA Transmitter Slicker Program FCC LicensedSpeed Central RepairsQuality Service Transmitter Checks Only includes GOLD/SILVER slicker$400 Transmitter & Receiver Calibration$2400 Frequency Upgrades & Changes crystals extra$2900 Bench Time Repairs per hour$2500 Transmitters service will receive AMA/RCMA sticker ADD $500 FOR SHIPPING & INSURANCE TURN AROUND TIME TWO WEEKS OR LESSIi UPSLJ ISA/MASTERCARD ACCEPTEDCOD Pea Patch/Shepherd Continued page 32 used form shape cowl Cut block inside dimensions sections AA B-B Epoxy B-B pattern side draw alignment lines foam properly position A-A pattern Glue A-A place shown picture Glue foam nose block A-A use 80- 100-grit sandpaper shape foam around patterns youre satisfied shape lay fiberglass cloth ever foam securing five-minute epoxy achieve snugness final one-hour epoxy used Youll need cut darts cloth good fit over form Try keep smooth possible avoid ex cessive sanding after epoxy applied Mix up batch Sig one-hour epoxy let soak fiberglass cloth using throwaway brush heat lamp hair dryer will speed up epoxy cure first coat dry knock off bumps rough spots coarse paper mix up apply second coat epoxy Sand 180-grit paper dry Use Sig glass beads epoxy Epoxilite have some handy fill low spots part smoothed satis faction cut away B-B hog out foam screwdriver Cut away A-A us ing Dremel-type tool router sand ing drum Glue F-lA front firewall along small hardwood blocks trial fit cowl trimming get flush fit fuselage sheeting Install en gine begin cutting away cowl fit over fit accurate screw cowl place Cut 2-in ring Lite Ply epoxy front cowl its centered engine shaft Glue rear block over stab sand shape Assemble tail wheel fittings epoxy tail wheel slot tail post Cevering finishing fuselage fin rudder covered Sig Koverall using nitrate dope wing stab/ele vator covered plastic film Dope brushed framework whereve covering contacted wood Stretc covering over fuselage th grain running crosswise lengthwise apply dope through covering t contact wood After tightening heat iron fabric given three coat nitrate clear Red Devil polyurethane almon shade gives original its cream cobs paint also sprayed th film holding up very well after mar flights black pinstriping A-i size Coverste Vinyl stick-on letterir office supply store used Pasture Pilots PPA logo t strictly tongue-in-cheek addition brought smile two seems amuse others notice logo w made Coverite Graphic Sheet thi painted old-timer cockpit ma Williams Bros 2%-in Sportsman simulate 1920s-style cap dabb baking soda small brush ad ed thin CyA repeating process until artful facsimile made bri piece A2 ply glued ti back cap rubberband used f elastic goggles After pinning windscreen place traced around its front ball-point pe carefully cut away covering #11 X-Acto knife leaving approximately /32 groove wood glued en Testors clear household c ment aluminum flange win screen made two strips Coven tape Which painted silver Frem initial inspiratien dna ing building stages finally relis ing its talents flier Ive received ma hours pleasure airplane Its realistic-looking model carries ne ism sky thats way enjo ing RC Pea Patch should satisfy Ha py touch-and-goes Radio Technique/Myers Continued page 36 can estimate current drawn ek tric motor dividing measured battery cap 150 Model Aviation ity time ran assuming run un dl power drops off unusable level example have 800-mAh battery motor runs six minutes average cur rent about 006 x mAli/minutes Average current 006 x 800 mAh/6 mm ps estimated 06 multiplier contains 60 minutes/ hour divided 1000 milliamps/amp make units come out right reasonable estimate because motor current almost constant thats due flat voltage/time discharge characteristic good Ni-Cd batteries can rearrange formula estimate bat tery capacity way acts service measure motor current ground see average about 10 amps find pack lasts five minutes air use ful capacity about amps x minutes/006 10 amps x 5 min/06 mAh no matter what label battery says can apply above formula radio bat teries 500-mAh pack flew plane two hours average current drawn 006 x 500 mAh/120 mm amps considering radio system service should keep mind oniy transmitter cur rent constant receiver current varies minimum current servos quiet about 10 amp maximum current sev eral servos working hard can sev eral amps depends number type servos connected receiver ihey used above learn make few con trol inputs necessary after low battery voltage detector tells batteries have discharged warning point less current demand likely have enough land formulas correct regardless number cells battery set up Airtronics Vision 8 Sail plane transmitter complex process friend John Clarke has spent much time learning spent time making videotape showing process step step separate illustrate process John has cluded some great Sailplane videos Order tape John F Clarke 911 Cov ert Ave New Hyde Park NY 11040 price $1995 plus $350 P&H New York residents add sales tax Narrow Banding/Smith Continued page 37 concentrate really practical equip ment five excellent Guidelinecertified FM radios available under $220 Six-channel models two brands commonly sold under $170 both outstanding high-quality val ues Now time fret about chang ing horses midstream brandwise Youll starting fresh some degree would probably good idea think twice about empowering collection old servos dictate new-equipment selec tions us careful approach narrow-banding can present serious sticker shock Establish plan begin im plement new-equipment purchase way youll get encourag ing taste flying least plane new rig experience will help keep narrow-banding program track Re-equipping pain theres no ques tion about concentrate what youll gain rather what youll giv ing up perhaps youll feel cheerful about abandoning much less-worthy gear Actually figure what renewed equipment will deliver length service factor security dandy new stuff can impart might come conclusion price youll pay could best RC investment youve ever made Its investment will come added payoff knowing youll well de fended battle frequencies Nineties may experience warm feeling about sacrifice will benefit fellow RCers Okay okayjust pretend didnt make last comment responding advertisers mention read about Model Aviation September 1990 151
Edition: Model Aviation - 1990/09
Page Numbers: 34, 35, 36, 150, 151
George M Mye Radio Thchnque 70 FmeIUd Fm Rd HIcksvllle NY 1801 ABSTRACT Reader letters intimate Ni-Cd de tails capacity formulas Caring Ni-Cd batter [ies Part 6Ni-Cd peculiarities FIRST letters 1 Walter H Rady Newport NH writes Dear GeorgeI am just getting started elec tric flight rging batteries properly single important thing con fused about articles have spelled out requirements very understandable way charger timer cutoff bat teries overcharged times result ant decrease capacity evident over months flew model already know what happens charger fails sends AC through batteries night left seven stainless steel tubes fuselage full white stuff class want compete doesnt allow battery charging during contest will charging overnight Cl 10 rate ques tion Can put pot leads Polks Multi-Charge-A-Matic charging cur rent can cut 90 mA will voltage drop detector still function Dear Walt Due Ni-Cd cell chemistry voltage drop detector VDD works fast charger could reduce cur rent built-in timer would keep interrupting charge no need VDD overnight charger complicate things would practical use some thing like Ace K/C DMVC purpose DMVC can powered 110 VAC 12 VDC will charge two packs up 10 cells independently rate select up 250 mA contains meter can set current accurately Part No 34K32C $5495 Ace K/C Inc PO Box SuE Higgins ville MO 64037 will find much information need Bob Kopskis K/C Electrics column will found few pages further 2 Now Tom McCowen Valley Ea gles RC Club Anchorage AK 99752 flyaway during Forty BelowThis Must Fun Fly January Everything seemed normal got plane back What can tell about effects low temperature Ni Cds Dear Tom Ni-Cd will deliver 100% ca pacity room temperature failing off higher lower temperatures Available charge drops TE off about one-half percent degree F below freezing data stops 40% loss -20F Half total loss occurs between 00 -20F can see subzero battery temper atures good Camera people work low temperatures keep batteries inside pocket between uses Before blaming batteries Id want see transmitter receiver stay aligned low temperatures Id also want see stiff servos hinges etc become low tem peratures 3 next ones Mike Tobin APO NY Dear George Ni-Cds deteriorate left discharged particular must charge new batteries buy can leave package Dear Mike Discharged Ni-Cds deteri orate stored room temperature main concern will accept full charge first time charged cant make up pack last minute expect much Ni-Cds must go through something like five charge/discharge cycles before can hold full charge first five charges should done overnight rate process takes time 34 Model Aviation 4 next question will long can Ni-Cd batteries stored Nobody knows sure answer depends strongly batteries used stored cells get old enough plate separator material deteriorates electro lyte evaporates may take 10 years idle storage cant inspect separator deterioration does show up loss capac ity Battery cyclers measure charge capacity put paper label pack test spring write test results date sticker see capacity has dropped significant amount cycle pack few times wont come back least 90% rat ing wont fly Other people may recommend battery replace ment 50% 80% rated capacity less may good number flashlight electric screwdriver evaluation considers risk have replace $25 battery pack three years have full capacity operate radio $1000 model will replace Just record dont clalm expert Electric flight nickle-cadmium batteries chargers So get information have aeronautical engineering degree enough additional study qualify degree electrical engineering have flown RC models 30 years time have studied bat tery manuals have tested various types chargers batteries Ive owned maintained couple electric cars boats including some reworking re winding motors Larry Sribnick has friend since started SR business flying buddy Bob Aberle has designed reviewed few Electric models took some data solved some problems During visits couple KRC Electric Fly-Ins amazed performances turned Dr Keith Shaw Bob Kopski others collected information Fast charg ers VDD timer cutoff seem norm have visited RC car tracks carpet rac ers run have observed winning driv ers spend much time testing cells malting socalled balanced packs Balanced packs assem bled cells exhibit similar characteris tics respect superior charge capacity discharge curve under tests Some drivers have computer-controlled test equipment buy batteries gross lots can pick out cells high side production tolerances makes sense have lot work before have battery ready race can buy balanced packs people supply carpet racers about twice price production-run packs pay additional testing SR packs Carpet race drivers use sophisticated fast charg ers VDD timer cutoff cooling fans blow packs being charged manuals say Ni-Cd batteries accept charge room temperature both higher lower temperatures reduce charge ac ceptance manuals also say heating cells charging bad Some hightech fast chargers use temperature sensor bur ied pack cut off fast charging whenever cell temperature rises fixed amount such 5 0C example RCA Hitachi portable VCR includes such charger Some carpet race drivers short exhausted Continued page 36 September 1990 35 RV-3 Deluxe Kit Need Only Join Wing Halves Install Tail Feathers Cover complete Hardware Package Included 88 wingspan G-38 G-62 engine sizes 17-20 lbs weight range information call write PO Box 299 Gonzales Texas 78629 512 672-7023 A\uthorized Ddio CntroI eivice Kraft West Coast Service Center Ohio 4I S SUPER CANOPY Giant 99 x 16 vinyl clad nylon canopy Red ow Blue e Color combo 95uauPm 1-3/8 rugged pipe frame 10 easy out steel tent stakes nylon guys Folds neat heavy duty cardboard box goes up quickly complete instructions Optional name city state printed ends 0 order canopy request additional information call write OHIO SUPERSTAR PRODUCTS Inc 216-223-1950 11376 Ridgeway Road Kensington ohio 44427 SQUARE CUT Tools __ 4073 254-0516 905 N Harbor C ty Blvd Melbourne FL 32935 Dealer/DIUlbuter Inqultius InvIted F da Pea data Add 6% Sales Ta, 36 Model Aviation packs resistive load store shorting resistor battery bug place battery bug assembly LED di ode resistors takes pack down about volt Either item supposed keep packs balanced None battery manufac turers agree procedure heres may have noticed cell discharge curves never go zero volts reason Any battery makes electricity chemistry stick penny nickle lemon will see voltage between coins Thats chem istry manufacturer assembles compo nents battery like sticking coins lemon voltage will appear between termi nals cell before charged voltage 06 VDC will continue long battery usable leave Ni-Cd battery shelf 10 years good cells will still read 06 09 VDC charge because chemistry chemistry helps hold electrolyte place Shorting cell 0 volts bad because pro motes creep leakage electrolyte out cell According Red Scholefield Gates En ergy Products manufacturers short out cells short-down/spring-back test weeds out weak cells short cell indi vidually 0 volts 24 hours re move short measure voltage cell doesnt spring back least 06 volts bad cell must discarded manuals say completely discharging pack time use cuts usable number charge/discharge cycles little one-third number cycles obtainable batter ies partially discharged before recharg ing want win car races thing want batteries last another Ive noticed situation kinds competition tests have shown battery tests use less unless duplicate end-use conditions example hobby cycler/charger will discharge battery drawing some amperage between 2C C/2 will cut off 11 09 volts per cell again respecting cell chemistry get number battety charge capacity useful transmitters receivers means absolutely nothing use same battery electric propulsion same test 10 amps endpoint volt per cell will measure smaller capacity manuals say apparent loss capac ity high discharge rates evidence cell de sign chemistry also say full ca pacity still can get out lower discharge rates have observed cell voltage rises rapidly after remove load produces heavy current drain supports view Battery construction makes difference use Sanyo cells orange red label high-current test will yield greater percentage rated capacity same test performed yellow-label cell other hand measure capacity af ter charged cell has storage month yellow-label cell may show 90% red-label cell shows 50% Thats labels have different colors doesnt end cells Using wrong plugs wires can reduce power delivered motor one-third So can overheating cell sol dering wire Continued page 150 WHEN YOU FORGET\OUR UNITS REMEMBER RC System NICd Batteries MI chargers need- padcagel Cycler-Charger *23996 Fits 48V Ra 96V Tx packsPlus $5 S&H Others available write call IRegular Model.. $4696 ForPlus $3 S&H11 ld kit sinaiPlus $3 S&H electric boat batteriesSpecIfy 612 24V Heavy Duty Model*6896 sport winch large boat andPlus $4 S&H electric power charging battenesSpecify 6 1 2V CaRa ProductsSASEIorS*tmaiionPO Box 221 605-9875924Dealersliwlied canton SD 57013 wnetner Ku OUIIUS[ suraiuii US SQUARE CUT Tools will save time Remove stubborn die cuts cut own squares slots Made US quality machined nickel plated steel Order set today See Daler Cataloger Order dont carry Sqsare cut Tools call us call well pay shipping US canada COD txtral ~~1~~I 209 645 5535 GOLDEN GATE HOBBIES PO BOX 27001 FRESNO CAUFORNIA 93729 M/CVISA OR COD HA TORI RA DICICON IMMSK HATORI BLUEPRINT SHOWS ALL EXHAUST ITEMS FULL SIZE 2FF X 4FT $ 5 WE WANT NEW DEALERS ! HATORI 650 LONG PIPE $4350 TO DEALERS CATALOG $ 200 OR FREE Will-I ORDERS Mere Fun less Funds ving pan62/2 inches Wing Area770 square inches Engine Size 10 cc 90 120 four stroke Designed AMA FAI Turn-around pattern Foam wing stab 3-32 Balsa sheet covering Tricycle conven lional gear fixed retracts Rear side exhaust fiber glass canopy Very positive maneuverable XLT SPECIFICA Wing Span65 inches Length65 inches Wing Area845 square inches Recommended Engine Size 10 cc 90 120 four stroke XLT designed tuned pipe re tract landing gears Capable AMA Turn-around pattern Rear side ex haust SPECIFICATIONS Wing Span Wing Area Engine Size 63Y4 inches 700 square inches 50-60 Glow 90 four stroke fun sport pattern turn-around can done Utter Chaos completely built up Balsa construction Canopy engine mount included years proven flying reliablity BRIDI AIRCRAFT DESIGNS INC 23625 Pineforest Lane Harbor City California 90710 213 549-8264 213 326-5013 SEE YOUR FAVORITE HOBBY SHOP OR RETAIL OUTLETW Dealer Inqurles Invited D&J ELECTRONICS 900 Lucy Road ll Ml 48843 546-2644 service makes RIO equipment utilizing state art electronics Spectrum Analyzer Precision Frequency Measuring equipment True 1991 Standards endorsed AMA & ROMA Transmitter Slicker Program FCC LicensedSpeed Central RepairsQuality Service Transmitter Checks Only includes GOLD/SILVER slicker$400 Transmitter & Receiver Calibration$2400 Frequency Upgrades & Changes crystals extra$2900 Bench Time Repairs per hour$2500 Transmitters service will receive AMA/RCMA sticker ADD $500 FOR SHIPPING & INSURANCE TURN AROUND TIME TWO WEEKS OR LESSIi UPSLJ ISA/MASTERCARD ACCEPTEDCOD Pea Patch/Shepherd Continued page 32 used form shape cowl Cut block inside dimensions sections AA B-B Epoxy B-B pattern side draw alignment lines foam properly position A-A pattern Glue A-A place shown picture Glue foam nose block A-A use 80- 100-grit sandpaper shape foam around patterns youre satisfied shape lay fiberglass cloth ever foam securing five-minute epoxy achieve snugness final one-hour epoxy used Youll need cut darts cloth good fit over form Try keep smooth possible avoid ex cessive sanding after epoxy applied Mix up batch Sig one-hour epoxy let soak fiberglass cloth using throwaway brush heat lamp hair dryer will speed up epoxy cure first coat dry knock off bumps rough spots coarse paper mix up apply second coat epoxy Sand 180-grit paper dry Use Sig glass beads epoxy Epoxilite have some handy fill low spots part smoothed satis faction cut away B-B hog out foam screwdriver Cut away A-A us ing Dremel-type tool router sand ing drum Glue F-lA front firewall along small hardwood blocks trial fit cowl trimming get flush fit fuselage sheeting Install en gine begin cutting away cowl fit over fit accurate screw cowl place Cut 2-in ring Lite Ply epoxy front cowl its centered engine shaft Glue rear block over stab sand shape Assemble tail wheel fittings epoxy tail wheel slot tail post Cevering finishing fuselage fin rudder covered Sig Koverall using nitrate dope wing stab/ele vator covered plastic film Dope brushed framework whereve covering contacted wood Stretc covering over fuselage th grain running crosswise lengthwise apply dope through covering t contact wood After tightening heat iron fabric given three coat nitrate clear Red Devil polyurethane almon shade gives original its cream cobs paint also sprayed th film holding up very well after mar flights black pinstriping A-i size Coverste Vinyl stick-on letterir office supply store used Pasture Pilots PPA logo t strictly tongue-in-cheek addition brought smile two seems amuse others notice logo w made Coverite Graphic Sheet thi painted old-timer cockpit ma Williams Bros 2%-in Sportsman simulate 1920s-style cap dabb baking soda small brush ad ed thin CyA repeating process until artful facsimile made bri piece A2 ply glued ti back cap rubberband used f elastic goggles After pinning windscreen place traced around its front ball-point pe carefully cut away covering #11 X-Acto knife leaving approximately /32 groove wood glued en Testors clear household c ment aluminum flange win screen made two strips Coven tape Which painted silver Frem initial inspiratien dna ing building stages finally relis ing its talents flier Ive received ma hours pleasure airplane Its realistic-looking model carries ne ism sky thats way enjo ing RC Pea Patch should satisfy Ha py touch-and-goes Radio Technique/Myers Continued page 36 can estimate current drawn ek tric motor dividing measured battery cap 150 Model Aviation ity time ran assuming run un dl power drops off unusable level example have 800-mAh battery motor runs six minutes average cur rent about 006 x mAli/minutes Average current 006 x 800 mAh/6 mm ps estimated 06 multiplier contains 60 minutes/ hour divided 1000 milliamps/amp make units come out right reasonable estimate because motor current almost constant thats due flat voltage/time discharge characteristic good Ni-Cd batteries can rearrange formula estimate bat tery capacity way acts service measure motor current ground see average about 10 amps find pack lasts five minutes air use ful capacity about amps x minutes/006 10 amps x 5 min/06 mAh no matter what label battery says can apply above formula radio bat teries 500-mAh pack flew plane two hours average current drawn 006 x 500 mAh/120 mm amps considering radio system service should keep mind oniy transmitter cur rent constant receiver current varies minimum current servos quiet about 10 amp maximum current sev eral servos working hard can sev eral amps depends number type servos connected receiver ihey used above learn make few con trol inputs necessary after low battery voltage detector tells batteries have discharged warning point less current demand likely have enough land formulas correct regardless number cells battery set up Airtronics Vision 8 Sail plane transmitter complex process friend John Clarke has spent much time learning spent time making videotape showing process step step separate illustrate process John has cluded some great Sailplane videos Order tape John F Clarke 911 Cov ert Ave New Hyde Park NY 11040 price $1995 plus $350 P&H New York residents add sales tax Narrow Banding/Smith Continued page 37 concentrate really practical equip ment five excellent Guidelinecertified FM radios available under $220 Six-channel models two brands commonly sold under $170 both outstanding high-quality val ues Now time fret about chang ing horses midstream brandwise Youll starting fresh some degree would probably good idea think twice about empowering collection old servos dictate new-equipment selec tions us careful approach narrow-banding can present serious sticker shock Establish plan begin im plement new-equipment purchase way youll get encourag ing taste flying least plane new rig experience will help keep narrow-banding program track Re-equipping pain theres no ques tion about concentrate what youll gain rather what youll giv ing up perhaps youll feel cheerful about abandoning much less-worthy gear Actually figure what renewed equipment will deliver length service factor security dandy new stuff can impart might come conclusion price youll pay could best RC investment youve ever made Its investment will come added payoff knowing youll well de fended battle frequencies Nineties may experience warm feeling about sacrifice will benefit fellow RCers Okay okayjust pretend didnt make last comment responding advertisers mention read about Model Aviation September 1990 151
Edition: Model Aviation - 1990/09
Page Numbers: 34, 35, 36, 150, 151
George M Mye Radio Thchnque 70 FmeIUd Fm Rd HIcksvllle NY 1801 ABSTRACT Reader letters intimate Ni-Cd de tails capacity formulas Caring Ni-Cd batter [ies Part 6Ni-Cd peculiarities FIRST letters 1 Walter H Rady Newport NH writes Dear GeorgeI am just getting started elec tric flight rging batteries properly single important thing con fused about articles have spelled out requirements very understandable way charger timer cutoff bat teries overcharged times result ant decrease capacity evident over months flew model already know what happens charger fails sends AC through batteries night left seven stainless steel tubes fuselage full white stuff class want compete doesnt allow battery charging during contest will charging overnight Cl 10 rate ques tion Can put pot leads Polks Multi-Charge-A-Matic charging cur rent can cut 90 mA will voltage drop detector still function Dear Walt Due Ni-Cd cell chemistry voltage drop detector VDD works fast charger could reduce cur rent built-in timer would keep interrupting charge no need VDD overnight charger complicate things would practical use some thing like Ace K/C DMVC purpose DMVC can powered 110 VAC 12 VDC will charge two packs up 10 cells independently rate select up 250 mA contains meter can set current accurately Part No 34K32C $5495 Ace K/C Inc PO Box SuE Higgins ville MO 64037 will find much information need Bob Kopskis K/C Electrics column will found few pages further 2 Now Tom McCowen Valley Ea gles RC Club Anchorage AK 99752 flyaway during Forty BelowThis Must Fun Fly January Everything seemed normal got plane back What can tell about effects low temperature Ni Cds Dear Tom Ni-Cd will deliver 100% ca pacity room temperature failing off higher lower temperatures Available charge drops TE off about one-half percent degree F below freezing data stops 40% loss -20F Half total loss occurs between 00 -20F can see subzero battery temper atures good Camera people work low temperatures keep batteries inside pocket between uses Before blaming batteries Id want see transmitter receiver stay aligned low temperatures Id also want see stiff servos hinges etc become low tem peratures 3 next ones Mike Tobin APO NY Dear George Ni-Cds deteriorate left discharged particular must charge new batteries buy can leave package Dear Mike Discharged Ni-Cds deteri orate stored room temperature main concern will accept full charge first time charged cant make up pack last minute expect much Ni-Cds must go through something like five charge/discharge cycles before can hold full charge first five charges should done overnight rate process takes time 34 Model Aviation 4 next question will long can Ni-Cd batteries stored Nobody knows sure answer depends strongly batteries used stored cells get old enough plate separator material deteriorates electro lyte evaporates may take 10 years idle storage cant inspect separator deterioration does show up loss capac ity Battery cyclers measure charge capacity put paper label pack test spring write test results date sticker see capacity has dropped significant amount cycle pack few times wont come back least 90% rat ing wont fly Other people may recommend battery replace ment 50% 80% rated capacity less may good number flashlight electric screwdriver evaluation considers risk have replace $25 battery pack three years have full capacity operate radio $1000 model will replace Just record dont clalm expert Electric flight nickle-cadmium batteries chargers So get information have aeronautical engineering degree enough additional study qualify degree electrical engineering have flown RC models 30 years time have studied bat tery manuals have tested various types chargers batteries Ive owned maintained couple electric cars boats including some reworking re winding motors Larry Sribnick has friend since started SR business flying buddy Bob Aberle has designed reviewed few Electric models took some data solved some problems During visits couple KRC Electric Fly-Ins amazed performances turned Dr Keith Shaw Bob Kopski others collected information Fast charg ers VDD timer cutoff seem norm have visited RC car tracks carpet rac ers run have observed winning driv ers spend much time testing cells malting socalled balanced packs Balanced packs assem bled cells exhibit similar characteris tics respect superior charge capacity discharge curve under tests Some drivers have computer-controlled test equipment buy batteries gross lots can pick out cells high side production tolerances makes sense have lot work before have battery ready race can buy balanced packs people supply carpet racers about twice price production-run packs pay additional testing SR packs Carpet race drivers use sophisticated fast charg ers VDD timer cutoff cooling fans blow packs being charged manuals say Ni-Cd batteries accept charge room temperature both higher lower temperatures reduce charge ac ceptance manuals also say heating cells charging bad Some hightech fast chargers use temperature sensor bur ied pack cut off fast charging whenever cell temperature rises fixed amount such 5 0C example RCA Hitachi portable VCR includes such charger Some carpet race drivers short exhausted Continued page 36 September 1990 35 RV-3 Deluxe Kit Need Only Join Wing Halves Install Tail Feathers Cover complete Hardware Package Included 88 wingspan G-38 G-62 engine sizes 17-20 lbs weight range information call write PO Box 299 Gonzales Texas 78629 512 672-7023 A\uthorized Ddio CntroI eivice Kraft West Coast Service Center Ohio 4I S SUPER CANOPY Giant 99 x 16 vinyl clad nylon canopy Red ow Blue e Color combo 95uauPm 1-3/8 rugged pipe frame 10 easy out steel tent stakes nylon guys Folds neat heavy duty cardboard box goes up quickly complete instructions Optional name city state printed ends 0 order canopy request additional information call write OHIO SUPERSTAR PRODUCTS Inc 216-223-1950 11376 Ridgeway Road Kensington ohio 44427 SQUARE CUT Tools __ 4073 254-0516 905 N Harbor C ty Blvd Melbourne FL 32935 Dealer/DIUlbuter Inqultius InvIted F da Pea data Add 6% Sales Ta, 36 Model Aviation packs resistive load store shorting resistor battery bug place battery bug assembly LED di ode resistors takes pack down about volt Either item supposed keep packs balanced None battery manufac turers agree procedure heres may have noticed cell discharge curves never go zero volts reason Any battery makes electricity chemistry stick penny nickle lemon will see voltage between coins Thats chem istry manufacturer assembles compo nents battery like sticking coins lemon voltage will appear between termi nals cell before charged voltage 06 VDC will continue long battery usable leave Ni-Cd battery shelf 10 years good cells will still read 06 09 VDC charge because chemistry chemistry helps hold electrolyte place Shorting cell 0 volts bad because pro motes creep leakage electrolyte out cell According Red Scholefield Gates En ergy Products manufacturers short out cells short-down/spring-back test weeds out weak cells short cell indi vidually 0 volts 24 hours re move short measure voltage cell doesnt spring back least 06 volts bad cell must discarded manuals say completely discharging pack time use cuts usable number charge/discharge cycles little one-third number cycles obtainable batter ies partially discharged before recharg ing want win car races thing want batteries last another Ive noticed situation kinds competition tests have shown battery tests use less unless duplicate end-use conditions example hobby cycler/charger will discharge battery drawing some amperage between 2C C/2 will cut off 11 09 volts per cell again respecting cell chemistry get number battety charge capacity useful transmitters receivers means absolutely nothing use same battery electric propulsion same test 10 amps endpoint volt per cell will measure smaller capacity manuals say apparent loss capac ity high discharge rates evidence cell de sign chemistry also say full ca pacity still can get out lower discharge rates have observed cell voltage rises rapidly after remove load produces heavy current drain supports view Battery construction makes difference use Sanyo cells orange red label high-current test will yield greater percentage rated capacity same test performed yellow-label cell other hand measure capacity af ter charged cell has storage month yellow-label cell may show 90% red-label cell shows 50% Thats labels have different colors doesnt end cells Using wrong plugs wires can reduce power delivered motor one-third So can overheating cell sol dering wire Continued page 150 WHEN YOU FORGET\OUR UNITS REMEMBER RC System NICd Batteries MI chargers need- padcagel Cycler-Charger *23996 Fits 48V Ra 96V Tx packsPlus $5 S&H Others available write call IRegular Model.. $4696 ForPlus $3 S&H11 ld kit sinaiPlus $3 S&H electric boat batteriesSpecIfy 612 24V Heavy Duty Model*6896 sport winch large boat andPlus $4 S&H electric power charging battenesSpecify 6 1 2V CaRa ProductsSASEIorS*tmaiionPO Box 221 605-9875924Dealersliwlied canton SD 57013 wnetner Ku OUIIUS[ suraiuii US SQUARE CUT Tools will save time Remove stubborn die cuts cut own squares slots Made US quality machined nickel plated steel Order set today See Daler Cataloger Order dont carry Sqsare cut Tools call us call well pay shipping US canada COD txtral ~~1~~I 209 645 5535 GOLDEN GATE HOBBIES PO BOX 27001 FRESNO CAUFORNIA 93729 M/CVISA OR COD HA TORI RA DICICON IMMSK HATORI BLUEPRINT SHOWS ALL EXHAUST ITEMS FULL SIZE 2FF X 4FT $ 5 WE WANT NEW DEALERS ! HATORI 650 LONG PIPE $4350 TO DEALERS CATALOG $ 200 OR FREE Will-I ORDERS Mere Fun less Funds ving pan62/2 inches Wing Area770 square inches Engine Size 10 cc 90 120 four stroke Designed AMA FAI Turn-around pattern Foam wing stab 3-32 Balsa sheet covering Tricycle conven lional gear fixed retracts Rear side exhaust fiber glass canopy Very positive maneuverable XLT SPECIFICA Wing Span65 inches Length65 inches Wing Area845 square inches Recommended Engine Size 10 cc 90 120 four stroke XLT designed tuned pipe re tract landing gears Capable AMA Turn-around pattern Rear side ex haust SPECIFICATIONS Wing Span Wing Area Engine Size 63Y4 inches 700 square inches 50-60 Glow 90 four stroke fun sport pattern turn-around can done Utter Chaos completely built up Balsa construction Canopy engine mount included years proven flying reliablity BRIDI AIRCRAFT DESIGNS INC 23625 Pineforest Lane Harbor City California 90710 213 549-8264 213 326-5013 SEE YOUR FAVORITE HOBBY SHOP OR RETAIL OUTLETW Dealer Inqurles Invited D&J ELECTRONICS 900 Lucy Road ll Ml 48843 546-2644 service makes RIO equipment utilizing state art electronics Spectrum Analyzer Precision Frequency Measuring equipment True 1991 Standards endorsed AMA & ROMA Transmitter Slicker Program FCC LicensedSpeed Central RepairsQuality Service Transmitter Checks Only includes GOLD/SILVER slicker$400 Transmitter & Receiver Calibration$2400 Frequency Upgrades & Changes crystals extra$2900 Bench Time Repairs per hour$2500 Transmitters service will receive AMA/RCMA sticker ADD $500 FOR SHIPPING & INSURANCE TURN AROUND TIME TWO WEEKS OR LESSIi UPSLJ ISA/MASTERCARD ACCEPTEDCOD Pea Patch/Shepherd Continued page 32 used form shape cowl Cut block inside dimensions sections AA B-B Epoxy B-B pattern side draw alignment lines foam properly position A-A pattern Glue A-A place shown picture Glue foam nose block A-A use 80- 100-grit sandpaper shape foam around patterns youre satisfied shape lay fiberglass cloth ever foam securing five-minute epoxy achieve snugness final one-hour epoxy used Youll need cut darts cloth good fit over form Try keep smooth possible avoid ex cessive sanding after epoxy applied Mix up batch Sig one-hour epoxy let soak fiberglass cloth using throwaway brush heat lamp hair dryer will speed up epoxy cure first coat dry knock off bumps rough spots coarse paper mix up apply second coat epoxy Sand 180-grit paper dry Use Sig glass beads epoxy Epoxilite have some handy fill low spots part smoothed satis faction cut away B-B hog out foam screwdriver Cut away A-A us ing Dremel-type tool router sand ing drum Glue F-lA front firewall along small hardwood blocks trial fit cowl trimming get flush fit fuselage sheeting Install en gine begin cutting away cowl fit over fit accurate screw cowl place Cut 2-in ring Lite Ply epoxy front cowl its centered engine shaft Glue rear block over stab sand shape Assemble tail wheel fittings epoxy tail wheel slot tail post Cevering finishing fuselage fin rudder covered Sig Koverall using nitrate dope wing stab/ele vator covered plastic film Dope brushed framework whereve covering contacted wood Stretc covering over fuselage th grain running crosswise lengthwise apply dope through covering t contact wood After tightening heat iron fabric given three coat nitrate clear Red Devil polyurethane almon shade gives original its cream cobs paint also sprayed th film holding up very well after mar flights black pinstriping A-i size Coverste Vinyl stick-on letterir office supply store used Pasture Pilots PPA logo t strictly tongue-in-cheek addition brought smile two seems amuse others notice logo w made Coverite Graphic Sheet thi painted old-timer cockpit ma Williams Bros 2%-in Sportsman simulate 1920s-style cap dabb baking soda small brush ad ed thin CyA repeating process until artful facsimile made bri piece A2 ply glued ti back cap rubberband used f elastic goggles After pinning windscreen place traced around its front ball-point pe carefully cut away covering #11 X-Acto knife leaving approximately /32 groove wood glued en Testors clear household c ment aluminum flange win screen made two strips Coven tape Which painted silver Frem initial inspiratien dna ing building stages finally relis ing its talents flier Ive received ma hours pleasure airplane Its realistic-looking model carries ne ism sky thats way enjo ing RC Pea Patch should satisfy Ha py touch-and-goes Radio Technique/Myers Continued page 36 can estimate current drawn ek tric motor dividing measured battery cap 150 Model Aviation ity time ran assuming run un dl power drops off unusable level example have 800-mAh battery motor runs six minutes average cur rent about 006 x mAli/minutes Average current 006 x 800 mAh/6 mm ps estimated 06 multiplier contains 60 minutes/ hour divided 1000 milliamps/amp make units come out right reasonable estimate because motor current almost constant thats due flat voltage/time discharge characteristic good Ni-Cd batteries can rearrange formula estimate bat tery capacity way acts service measure motor current ground see average about 10 amps find pack lasts five minutes air use ful capacity about amps x minutes/006 10 amps x 5 min/06 mAh no matter what label battery says can apply above formula radio bat teries 500-mAh pack flew plane two hours average current drawn 006 x 500 mAh/120 mm amps considering radio system service should keep mind oniy transmitter cur rent constant receiver current varies minimum current servos quiet about 10 amp maximum current sev eral servos working hard can sev eral amps depends number type servos connected receiver ihey used above learn make few con trol inputs necessary after low battery voltage detector tells batteries have discharged warning point less current demand likely have enough land formulas correct regardless number cells battery set up Airtronics Vision 8 Sail plane transmitter complex process friend John Clarke has spent much time learning spent time making videotape showing process step step separate illustrate process John has cluded some great Sailplane videos Order tape John F Clarke 911 Cov ert Ave New Hyde Park NY 11040 price $1995 plus $350 P&H New York residents add sales tax Narrow Banding/Smith Continued page 37 concentrate really practical equip ment five excellent Guidelinecertified FM radios available under $220 Six-channel models two brands commonly sold under $170 both outstanding high-quality val ues Now time fret about chang ing horses midstream brandwise Youll starting fresh some degree would probably good idea think twice about empowering collection old servos dictate new-equipment selec tions us careful approach narrow-banding can present serious sticker shock Establish plan begin im plement new-equipment purchase way youll get encourag ing taste flying least plane new rig experience will help keep narrow-banding program track Re-equipping pain theres no ques tion about concentrate what youll gain rather what youll giv ing up perhaps youll feel cheerful about abandoning much less-worthy gear Actually figure what renewed equipment will deliver length service factor security dandy new stuff can impart might come conclusion price youll pay could best RC investment youve ever made Its investment will come added payoff knowing youll well de fended battle frequencies Nineties may experience warm feeling about sacrifice will benefit fellow RCers Okay okayjust pretend didnt make last comment responding advertisers mention read about Model Aviation September 1990 151