Radio Technique George M Myers INTERFERENCE TESTS morn ing received mail copies corres pondence between Mr Geoffiey E Styles Director Public Relations AMA HQ Mr George M Weigman Secretaiy Lake Shore RC Club Illinois gist members Lake Shore RC Club cooperated attempt discover minimum spacing between two RC fieldsthat minimum situation test plan written tests executed using standard RC equipment CR communication automobile distance measurement test air planes orbited Lake Shore RC Club field various altitudes 400 1500 feet presume no airfields man-carrying aircraft nearby de liberate attempts made interfere using same-channel transmitters speci fied distances log tests does indicate whether RC equipment AM mix AM FM addition no map no measurements reported transmitter output power frequency accuracy Therefore cant comment conclusions relate special case anyway can use space applaud initiative planning executing tests find data suit needs now would please hear readers likewise next urge share findings us After meaning word academy place teaching special skills concur Lake Shore RC Club recommendation Inter-field interfer ence testing should conducted assure neither geographical features between RC fields nor use various kinds equipment will produce interference con ditions Hills can shield power lines can bring interference absence testing stick AMA recommendation five miles between fields safetys sake Take note comment field CR difficulty reaching mobile CR times complicated test Based experience might want use intermediate relay station stations obtain positive communi cations same power lines hills large metal structures like bridges long metal fences variations antenna alignments etc produce unexpected results CR likewise RC systems following Lake Shore RC Club members deserve Attaboy AMA initiative planning conducting tests Bob Bentley John Snow Jr Ion Torgerson Deo Cri Dennis Bielich Jim Leman Les Seibert Norm George John Snow Sr George Wieg man Lynn Stevens Rich Woodruff Don McCourt Roger Hallum bother test anyway might wonder spend much column space subject interference Some folks never see problem Others cant get away instance hear com plaints club meetings letters phone calls received over US cars boats running aircraft fre quencies Cars particular have explosion popularity Bob Novak No vak Electronics told 95% production now goes cars esti mates 2000000 RC cars now use Hand-in-hand complaints misuse RC channels come complaints about hobby store owners fail tell RC system buyers about existence RC Frequencies Allocations Federal Law restricting 72 MHz frequen cies Aircraft Only 75 MHz fre quencies Non-Aircraft Use except shared frequencies 7216072320 72960 Aircraft Only frequency 75640 MHz What can about cry collective noun meaning AMA first place must accept fact hobby dealer has neither authority nor responsibility control anRC system used once leaves store Hobby dealers may spend time explaining frequency allocations instead making sale no law compel dont want Next should remember no RCer has right fly Flying privilege gained goodwill created half-century actions other model builders very few flew RC little bad feeling generated stupid individual can undo thousands modeler-years good work two people show up same place time RC systems same channel argument develops has greater privilege regarding simultaneous operation aircraft non-aircraft RC channel designated FCC Aircraft Only fact Federal Law pre-exists dispute will give aircraft operator winning edge police summoned airplane people can produce up-to-date copy FCC Regulation 95 Part E 36 Model Aviation Lets hopethatthe exhaust smoke Jocy Kusterbeckschoppershows up well whenthis photo printed magazinebecause gives excellent visualization what goes Helicopter hovering Ground Effecti exhaust plume rises toward rotor disk before being blown toward ground thereby demonstrating Helicopters need extra power hovering near ground high-pressure region uriderthe main rotor takes doughnut shape because no rotor-blade area centerof disk force air downward ground near main mass descending airflow reflected up through center disk reducing swept biade area supports machine effect disappears rotordiak isi -2 diametersabove ground can Calling police can turn argument feud need Faced situation ask yourself What would prudent man Perhaps thats neces saryis get some l0 copies AMA Frequency Plan AMA HQ give offenders front witnesses possible fails obtain compliance want might show document owner building lot lake transgressions taking place Sometimes makes difference educate Non-Airctuft people running field pond thats too close flying field can some testing own using Aircraft Only frequencies ask change crystals may have some Pur ple/White Blue/White Yellow/White crystal sets can use place illegal crystals offer exchange crystals thereby elimi nate problem frequencies 72160 72320 72960 MHz will continue legal boats cars till December 20 1987 Crystal-swapping RC system owners has legal since November 1984 crystal swapping legal f trans mitter shows legal emission characteris tics after swap Very few RC system owners have equipment know ledge verifr emission characteristics said equipment knowledge results crystal-swapping can ille gal Ponder AMA Frequency Committee set up Frequency Plan corres ponded AMYA MYRA ROAR other Non-Aircraft organizations agreed teach members respect law None sanction use Aircraft Only frequencies com petitions regardless whether aircraft likely affected Appeal organizations applicable assistance resolving problems just might surprised help get else fails aircraft owners can build some boats cars join fun might enjoy also possible will make such crowd win races original sinners will go some else Besides become voting member club get opportunity introduce club rules procedures want Vote own man presidency get control treasury never knows what can done until tries have other bright ideas complaints hear have common theme force hobby dealers sell Airplane Only RC systems airplanes have covered thought already hobby dealers authority regulate uses RC systems wouldnt able get job done Because stands now bands arent purely Air craft Only Non-Aircraft Only Some 72 MHz radios can used both Aircraft Non-Aircraftlegally offenders can legitimately claim confusion situation could improve 1988 72 MHz legally becomes Aircraft Only 75 MHz becomes Non-Air craft Only wont cause incomprehensible frequencyflag system comes down Nobody will keep 68 flag color groups multiple duplications straight minds stick multicolored flags give everybody built-in excuse claiming confused look much simpler prob lem would dealer two kinds flag sale Red ones stamped 72 MHz Airplane Use Only Green ones stamped 75 MHz Non-Aircraft Use Onlystamped factory logical thing to begin training people identify RC channels number intended begin ning Some people dont want refer channels number have way deal give aflag system color band such flag everyone will have pay attention number boards can review Single-Color Flag page 128 1984-85 rule book As see single-color flag system should adopted right now flag system published immediately take effect January 1 1988 completely replace present multicolored flag sys tem have made recommendation AMA Frequency Committee Ex ecutive Council agree write district VP AMA HQ say December 20 1987 crossovers uses between 72 75 MHz groups will disappear making time logical flag change sooner get started making change manufac turer level sooner situation will improved level Remember flak got 1983 related flag system its late publication made impossible manufacturers have flags market time needed presume existing stocks ribbons could used up attrition 27 49 MHz 6-meter fliers Normally flag gets worn dirty two years use start SingleColor Flag idea right now changeover can made smoothly 1988 make move single-color flag now time right can cut out another problem already nuisance due get worse problem now can have two guys trying fly same channel eg RC40 because has wrong clip ie Black/Yellow 534 instead ofYellow/Black RC4O already happens too frequently ignored continue invite mistakes George M Myers 70 Froehlich Farm Rd Hicksvzlle NY 11801 Flying Near Al rports Careful June 1985 37 Safe Flying No Accident Tom Hunts finger rests atop receiver antenna AMAs 926 MHz receiver Hi-Tech 2002 piane AMA stiii activeiy pursuing acquisition possible exciusive 900 MHz channels RC ever comes pass advantages wiii shorter tennas ail aroundtake iook fuiiy-extended transmitter antenna beiow pianel
Edition: Model Aviation - 1985/06
Page Numbers: 36, 37
Radio Technique George M Myers INTERFERENCE TESTS morn ing received mail copies corres pondence between Mr Geoffiey E Styles Director Public Relations AMA HQ Mr George M Weigman Secretaiy Lake Shore RC Club Illinois gist members Lake Shore RC Club cooperated attempt discover minimum spacing between two RC fieldsthat minimum situation test plan written tests executed using standard RC equipment CR communication automobile distance measurement test air planes orbited Lake Shore RC Club field various altitudes 400 1500 feet presume no airfields man-carrying aircraft nearby de liberate attempts made interfere using same-channel transmitters speci fied distances log tests does indicate whether RC equipment AM mix AM FM addition no map no measurements reported transmitter output power frequency accuracy Therefore cant comment conclusions relate special case anyway can use space applaud initiative planning executing tests find data suit needs now would please hear readers likewise next urge share findings us After meaning word academy place teaching special skills concur Lake Shore RC Club recommendation Inter-field interfer ence testing should conducted assure neither geographical features between RC fields nor use various kinds equipment will produce interference con ditions Hills can shield power lines can bring interference absence testing stick AMA recommendation five miles between fields safetys sake Take note comment field CR difficulty reaching mobile CR times complicated test Based experience might want use intermediate relay station stations obtain positive communi cations same power lines hills large metal structures like bridges long metal fences variations antenna alignments etc produce unexpected results CR likewise RC systems following Lake Shore RC Club members deserve Attaboy AMA initiative planning conducting tests Bob Bentley John Snow Jr Ion Torgerson Deo Cri Dennis Bielich Jim Leman Les Seibert Norm George John Snow Sr George Wieg man Lynn Stevens Rich Woodruff Don McCourt Roger Hallum bother test anyway might wonder spend much column space subject interference Some folks never see problem Others cant get away instance hear com plaints club meetings letters phone calls received over US cars boats running aircraft fre quencies Cars particular have explosion popularity Bob Novak No vak Electronics told 95% production now goes cars esti mates 2000000 RC cars now use Hand-in-hand complaints misuse RC channels come complaints about hobby store owners fail tell RC system buyers about existence RC Frequencies Allocations Federal Law restricting 72 MHz frequen cies Aircraft Only 75 MHz fre quencies Non-Aircraft Use except shared frequencies 7216072320 72960 Aircraft Only frequency 75640 MHz What can about cry collective noun meaning AMA first place must accept fact hobby dealer has neither authority nor responsibility control anRC system used once leaves store Hobby dealers may spend time explaining frequency allocations instead making sale no law compel dont want Next should remember no RCer has right fly Flying privilege gained goodwill created half-century actions other model builders very few flew RC little bad feeling generated stupid individual can undo thousands modeler-years good work two people show up same place time RC systems same channel argument develops has greater privilege regarding simultaneous operation aircraft non-aircraft RC channel designated FCC Aircraft Only fact Federal Law pre-exists dispute will give aircraft operator winning edge police summoned airplane people can produce up-to-date copy FCC Regulation 95 Part E 36 Model Aviation Lets hopethatthe exhaust smoke Jocy Kusterbeckschoppershows up well whenthis photo printed magazinebecause gives excellent visualization what goes Helicopter hovering Ground Effecti exhaust plume rises toward rotor disk before being blown toward ground thereby demonstrating Helicopters need extra power hovering near ground high-pressure region uriderthe main rotor takes doughnut shape because no rotor-blade area centerof disk force air downward ground near main mass descending airflow reflected up through center disk reducing swept biade area supports machine effect disappears rotordiak isi -2 diametersabove ground can Calling police can turn argument feud need Faced situation ask yourself What would prudent man Perhaps thats neces saryis get some l0 copies AMA Frequency Plan AMA HQ give offenders front witnesses possible fails obtain compliance want might show document owner building lot lake transgressions taking place Sometimes makes difference educate Non-Airctuft people running field pond thats too close flying field can some testing own using Aircraft Only frequencies ask change crystals may have some Pur ple/White Blue/White Yellow/White crystal sets can use place illegal crystals offer exchange crystals thereby elimi nate problem frequencies 72160 72320 72960 MHz will continue legal boats cars till December 20 1987 Crystal-swapping RC system owners has legal since November 1984 crystal swapping legal f trans mitter shows legal emission characteris tics after swap Very few RC system owners have equipment know ledge verifr emission characteristics said equipment knowledge results crystal-swapping can ille gal Ponder AMA Frequency Committee set up Frequency Plan corres ponded AMYA MYRA ROAR other Non-Aircraft organizations agreed teach members respect law None sanction use Aircraft Only frequencies com petitions regardless whether aircraft likely affected Appeal organizations applicable assistance resolving problems just might surprised help get else fails aircraft owners can build some boats cars join fun might enjoy also possible will make such crowd win races original sinners will go some else Besides become voting member club get opportunity introduce club rules procedures want Vote own man presidency get control treasury never knows what can done until tries have other bright ideas complaints hear have common theme force hobby dealers sell Airplane Only RC systems airplanes have covered thought already hobby dealers authority regulate uses RC systems wouldnt able get job done Because stands now bands arent purely Air craft Only Non-Aircraft Only Some 72 MHz radios can used both Aircraft Non-Aircraftlegally offenders can legitimately claim confusion situation could improve 1988 72 MHz legally becomes Aircraft Only 75 MHz becomes Non-Air craft Only wont cause incomprehensible frequencyflag system comes down Nobody will keep 68 flag color groups multiple duplications straight minds stick multicolored flags give everybody built-in excuse claiming confused look much simpler prob lem would dealer two kinds flag sale Red ones stamped 72 MHz Airplane Use Only Green ones stamped 75 MHz Non-Aircraft Use Onlystamped factory logical thing to begin training people identify RC channels number intended begin ning Some people dont want refer channels number have way deal give aflag system color band such flag everyone will have pay attention number boards can review Single-Color Flag page 128 1984-85 rule book As see single-color flag system should adopted right now flag system published immediately take effect January 1 1988 completely replace present multicolored flag sys tem have made recommendation AMA Frequency Committee Ex ecutive Council agree write district VP AMA HQ say December 20 1987 crossovers uses between 72 75 MHz groups will disappear making time logical flag change sooner get started making change manufac turer level sooner situation will improved level Remember flak got 1983 related flag system its late publication made impossible manufacturers have flags market time needed presume existing stocks ribbons could used up attrition 27 49 MHz 6-meter fliers Normally flag gets worn dirty two years use start SingleColor Flag idea right now changeover can made smoothly 1988 make move single-color flag now time right can cut out another problem already nuisance due get worse problem now can have two guys trying fly same channel eg RC40 because has wrong clip ie Black/Yellow 534 instead ofYellow/Black RC4O already happens too frequently ignored continue invite mistakes George M Myers 70 Froehlich Farm Rd Hicksvzlle NY 11801 Flying Near Al rports Careful June 1985 37 Safe Flying No Accident Tom Hunts finger rests atop receiver antenna AMAs 926 MHz receiver Hi-Tech 2002 piane AMA stiii activeiy pursuing acquisition possible exciusive 900 MHz channels RC ever comes pass advantages wiii shorter tennas ail aroundtake iook fuiiy-extended transmitter antenna beiow pianel