PIC interface and JR

[tarts]

Hi
I made this fms interface


It's similar to this one that comes with FMS but it uses pic12f629 instead 12c508. I used the hex that could be found on this page:


It worked well with my futaba radio transmitter but have anyone used it with JR. I have jr x-378 transmitter and it just doesn't work, calibration doesn't move at all.

Can anyone help me??

[Steve Lewin]

Do you have the Tx connected what looks like the wrong way round ? i.e. tip of jack to ground, sleeve to signal in. That works better with some ccts because JR trainer signals are inverted WRT Futaba and are also capacitively couple so they float.

On some circuits I've also found I needed to switch R5 so it connects base to +ve rather than to ground. It won't do any harm so I guess it's worth a try.

Steve

[tarts]

[Steve Lewin]

[tarts]

Yes I don't swich my transmitter on.

I connected R5 to the vdd like you said but now the channels are jumping and twiching and doesn't respond to the tx

Now I have already made circuit.It's said that it works with Futaba, Hitec, JR.
Same story futaba works but JR not, only twiching and jumping.

What to do?

[Steve Lewin]

It may be that the trainer skt on your JR simply doesn't work. Can you look at the signal with an oscilloscope or have you tried it in trainer mode with another Tx ?

Are you using a mono or stereo jack ? It should be mono but I've heard that some JR Txs don't connect well with mono jack plugs. I've never seen that myself but it might be worth checking the contacts inside the Tx.

Steve

[tarts]

I checked the signal with oscilloscope and compared it with futaba.Futabas was ok but JRs was a mess
It turned out that my tx was in pcm mode not ppm.Finally it WORKS.

Thanx a lot.