Dennis Travassaros shares with us some of his thoughts on the nature of radio interference and its effect.
What are radio waves and where are they?
· You cannot see radio waves, just as you cannot see the output of your Radio Control transmitter;
· They exist on a multitude of frequencies / bands
· They exist anywhere a mobile phone, radio, or TV works
· If they were opaque, you’d be lucky to see 5 feet ahead
· The ACMA website allows you to search by postcode, and you will see emissions exist everywhere www.acma.gov.au
What exists around our club?
phone network and transmission
What is the effect of radio interference?
signals on the same frequency confuses a receiver, and a confused receiver
is likely to mean no control over your model
o They can hold controls rather than allow random effects on loss of signal by receiver
o They need to be preset/programmed, and you must turn the transmitter on before receiver
o There are peculiarities, eg. throttle reverse might give full throttle rather than no throttle if failsafe isn’t programmed last
o Tests the overall output of transmitter, but primarily the output module and crystal
o If you change crystals / frequency, you need to recertify
o ‘V’ marking means the transmitter is certified variable, and can accept different, certified, modules (certified in same transmitter)
o Wipe aerial clean regularly; talk to a radio technician regarding sprays
o Service / certify transmitter every 2 years at a minimum
o Field tests: some debate, but always do a range check as a matter of course after any changes or problems
· Setting up
o Separate receiver aerial from other electronics (Receiver aerial must be fully extended, not coiled)
o Refer to radio manufacturer’s instructions, they’re there to help
o Handle with care, don’t pull on leads (grasp the plugs)
o Run suppression (electric models)
o Take extra care with digital servos (high current drain) and tail servos (be careful with long leads, particularly close to aerial)
o Test your nicads before, during, and after a day at the field
What to do if you experience interference in flight
· Hold transmitter high with aerial vertical (flying thumb and finger can make it easier)
· Call to see if another transmitter was just turned on, if yes, yell please turn it off immediately
· When any control works use it and pretend it’s a dead stick, kill the engine / glide down safely, away from spectators if possible
· The closer the model gets, the more control you’ll have, aim for the field, but well away from spectators.
· Don’t give up, fight to keep control, models have landed safely behind trees
· Even if you’ve no chance of saving the model / equipment, try to kill the throttle, and land or crash without further loss or injury
· Analyse the incident objectively, get equipment checked by technician, try and find a real cause, look to more experienced pilots for help
*** 31 December, 2016 11:36 PM +1100 ***
Last updated 31 December, 2016