Author Topic: Troubleshooting T9CP Futaba 35mhz (Read 726 times)

zeke-zero · « **on:** June 23, 2013, 11:02:28 PM »

Hi there,

I'm a newbie to 35mhz and recently purchased a t9cp tx from a forum member.

I bought an FP-R138DF 8ch rx from EBay and a set of CH56 Futaba xtals.

My first mistake was getting 'white label' single conversion xtals.

I was advised to get a set of orange label dual conversion crystals. Whilst looking for both tx and rx with the orange label it became apparent there was a shortage of tx dual conversion crystals. I then read that Futaba don't produce dual conversion tx crystals as only the receiver is dual conversion?

To cut a long story short I am getting some serious glitches when trying to operate the radio.

I plug my BEC into CH3 or CH8/B of the rx. Then any one of the servos to any of the remaining channels 1-4.

The servo pulses fast (about 4hz) and will continue pulsing until the tx is switched off. It will respond to movement of the controls (not in a linear way that I can tell, but I can hear movement that corresponds to the stick moving).

I have tried pluging the speed controller input into other rx channels but the results are the same.

Can anybody explain what I'm doing wrong or is it that my equipment faulty or incompatible?

Specs:

Tx T9CP - std config. Fitted with TW-FM RF module and ch56 WHITE LABEL crystal
Rx FP-R138DF. Fitted with ch56 ORANGE LABEL dual conversion crystal
BATTERY: Turnigy 3c 2200mah
Speed Controller: Hobbyking A-ZTW 35a
Servos: hobbyking sub micro

Thanks,

zeke

bigMouse · « **Reply #1 on:** June 23, 2013, 11:59:02 PM »

Press and hold down: <Mode/Page> button to get the menu.
Select <cursor down> arrow to get screen which lists <Parameter>
Select <Parameter> using the wheel, then press.
<Down arrow> to <MODUL> (probably showing PPM)
Turn the wheel to select PCM.
It will show Cycle power? press.

zeke-zero · « **Reply #2 on:** June 25, 2013, 06:09:57 PM »

Thanks, worked it out 10 mins after posting

.

Got my ESC to work with the radio gear as well. Terribly glitchey when flying though- could make the motor spin momentarily just by fiddling with the antenna on the tx??

Response felt a bit laggy as well?

Think I might just revert to a new Turnigy 9xr with module?

bigMouse · « **Reply #3 on:** June 25, 2013, 06:34:06 PM »

PCM is well renowned for lack of glitching, so there is obviously something wrong with your gear!

Assuming the Tx and Rx is ok, I'd would be looking at:

Use Futaba xtals, don't use xtals from another make.
Replace xtals (make sure they are both on the same channel) they suffer from heavy impacts.
If the Rx is not new, open the case and check the antenna wire is still soldered to the pcb.
Check the Tx antenna is screwed down in place (test by hand)
Try the rx with a mimn or nicad, some cheap ubecs are very noisy.
The Rx antenna must not pass very close to metal things like the battery, it doesn't matter where it exits the Rx but very important further along the antenna.
Check your leads and connectors.