Super Cub Tx/Rx problems

[grubbyjeans]

I've been experiencing severe, sporadic transmitter problems. Sometimes in pre-flight check the control servo jitters and at other times the motor shuts off. I've had it happen both on the ground and just before the crash

I've gone through all the connectors on the receiver and the radio and have found no loose connections.

The video you are about to see, I hope, is with new batteries in the Tx, 11.5v. The flight battery was freshly charged, 10.1v at installation. The radio is open with the speed slider is in the 'cruise' position, and the stick is not contacting any surface and therefore isn't being moved.

Watch the video and HELP!!!
rnew.lonestarfieros.org/SuperCub/RadioTest.wmv

Thanks

grubby

[davemac2]

does your hand moving actually affect it? ie. does it do this even if you don't put your hand near the transmitter? If it does it with your hand, then your hand may be acting lke a reflector and affecting the transmission power. That would imply either a mistuned Tx or Rx, or the Rx antenna is broken, or the Tx antenna is loose at its base or not making proper contact with the PCB. What happens if you put the Tx right beside the plane? Do you get more consistent operation?

dave mc

[hack73]

Nice! I been looking for a hands free transmitter...hahaha. Very strange. Never seen this before with any electronic device. If I come across anything on the Web, I'll let you know...Good luck.

[grubbyjeans]

davemac2 said:

does your hand moving actually affect it? ie. does it do this even if you don't put your hand near the transmitter? If it does it with your hand, then your hand may be acting lke a reflector and affecting the transmission power. That would imply either a mistuned Tx or Rx, or the Rx antenna is broken, or the Tx antenna is loose at its base or not making proper contact with the PCB. What happens if you put the Tx right beside the plane? Do you get more consistent operation?

dave mc

I can't say for certain that my hand was causing the action, but it surely seemed to. The plane was on the floor, just a couple of feet from the antenna.

I opened the radio to search for cold solder joints. The antenna mount is tight and had a good connection. I tried pressing on the board and torquing the system but could find no faulty solder pads or loose components. If it were a more expensive radio, I'd have it checked, but I'm just going to step up to a 'real' TX.

I'd had problems with the radio for a couple of days. Sometimes it would fly without problems, then suddenly this. The last time I took it out, it would completely loose power and would not respond to any action from the radio. I tried waving the antenna over the plane and the motor would just run in short bursts.

I also discovered that I could put pressure on the switches, any of the switches, and the motor would spin for just a few turns.

I think that either radio or receiver has gone south on me.

I'm going to swap to a better radio anyway. I want a radio that I can use both on my SCs and a kit I am going to build. I'm going to put ailerons on one of my SuperCubs so I can learn to fly with them before I fly my kit.

grubby