Nitehawk

While flying my recently completed RYAN STA, It acted erratically: engine speed suddenly went full throttle, an aileron caused a quick bank,. I immediately got her down. Upon running the engine with the plane secured, and waving the xmtr ant around, similar erratic action occured. I removed the wing, thinking that the flying wires may be the cause. No change, but while touching the ant on one of the flying wires(wing now on the ground by itself) erratic operation of servos seemed to be amplified. Futaba Gpld FG xmtr with Futaba r128 receiver. I had only flown this plane on its maiden flight 2 months ago, with no incidences. Of course, Futaba no longer services these devices. What to do?[>:]

i4c

www.radiosouthrc.com

These guys can checkout your system. They do regular radio tune-ups and years in business.

Rod

canadagoose

My Feedback: (2)

I've been having a problem like yours as well. It first started with my plane suddenly banking quickly to the left for a split second. The last flight i thought i was going to lose all control of it, glitching seemed to affect the throttle,elevator and ailerons. I won't fly it anymore like it is, but i did fly it in three different places in the province that are far away from each other, it experienced glitching in all three places, i think i can rule out interference. It's not my TX because i've flown a different plane on the same channel with the transmitter but with a different reciever and it never experienced any glitching. I guess that would leave the RX as the prime suspect or maybe the battery or the switch. I can never get it to do it on the ground with the antenna up. I can only get some erratic servo movement if i have the antenna collapsed and wave the transmitter back and forth. I'm going to try using my other reciever in the plane near future. Nighthawk, if you find out the cause of your problem please post it because it might help me as well, I'll do the same as well if i find the cause of my problem.

canadagoose

My Feedback: (2)

I did a test with my transmitter and the two RX's I put the transmitter on the ground about 30 feet away from the plane with the antenna collapsed and pointing away from the RX, the servos twitched alot when hooked up to the RX that was in the plane that had the gliching but were solid as a rock when hooked up to the other RX. I made sure that the antennas were in the same position when the recievers were tried. I guess it looks like i have a bad reciever. I think i might try soldering in a new antenna wire first then try it again.

Nitehawk

I have sent my receiver and two xmtrs to a service shop for a checkup. In the meantime another flyer in our club started experiencing similar effects with his Futaba xmtr and a GWS rcvr in an electric combat wing. He bought a new MCI rcvr and experienced the same. Problem remains. I will report any findings .

Nitehawk

I sent my xmtr and rcvr to a guy who checks them out, calibrates the I.F., checks modulation indexes and RF output. He found a problem in my rcvr IF tank circuit where an intermittant, vibration sensitive component was causing the demodulated output to cause erratic output to the servos. He recommended retiring it for another rcvr. With the frequency alignment and checkout, he believes all will be well, now.