GarryM

I have a Futaba 9C and I read a lot about not leaving the antenna fully collapsed when it is on.
This brings up the question about range checking.
Should the antenna be FULLY collapsed when range checking or should it be extended just one section so that it is not down behind the module?

Thanks for your advice.
Garry

squareloop

My Feedback: (1)

It's when you have the radio on for more than the few minutes to do a range check is when it becomes detrimental I suppose. The manual says to do it that way anyway.

I recently left my 9C on by accident with the antenna collapsed for 3 hours. I ranged checked a couple of days later and it was OK. But I'll never do that again if I can help it.

BackAfter20

My Feedback: (5)

I have the 9C, also, and had the same question. There is a thread somewhere in here that addresses it. The answer is to fully collapse the antenna when range checking.

Damage supposedly only occurs when the antenna is fully collapsed for prolonged periods with the transmitter on.

Rodney

I assume you are talking about PPM (not PCM). If so, you are caught between two evils; yes, the transmitter output stage is being stressed when you run with the antenna down, the energy that would normally be radiated is being dissipated as heat in the final output stage. If you limit the time to as short as possible, no harm should be done. What is that time?>hard to say but I try to limit it to 1 minute if possible. Of course a safer way is to test with the antenna up but it would cause you to move an unreasonable distance from the receiver (impractical to say the least) so, just run with the antenna colapsed for as short a time as possible. PCM requires a different procedure for range checking, one of simpler ways is to check with the engine running at higher than idle then back away until failsafe kick in. Now approach the receiver until the engine picks up again (responding to your input) and that is your safe range check.

strato911

Rodney - the only difference in range checking PCM vs PPM is how to identify loss of signal. Both are done with the antenna fully collapsed, and then find the threshold where signal is lost / regained.

Reminder - whenever performing range checks with engine running (PPM or PCM), either have someone holding the plane, or secure it well enough to hold it even at full throttle.

JohnBuckner

My Feedback: (1)

A range check not done with the engine running and cycled up to full throttle is just one step above being useless.

It is a long list of evil gremlins that can hide in your airborne system and will not show themselves untill under the influence of vibration.

Its a common occurance to watch someone that thinks not, to range check OK without running the engine and then proceed to launch into obvious radios problems.

John

GarryM

I suspected that having it collapsed for a brief period while range checking was OK but wanted to get a few opinions on it.

I don't see very many folks at our field range checking. The instructors will have tranees do range checks but most others don't do it.

I Just got my wings a few weeks ago and I am trying to form some good habits so I range check at the beginnig of each session and check my Rx battery (under load) after each flight.

Thanks for the advice.
Garry