RC transmission through tether

[mikec]

There have been a number of projects to read ppm, but it involves quite complex programming skills so I was looking for useful code.The reason I want to go with the existing control is that it will only need one wire to carry the signal. Also, having splashed out quite a lot of money (for me) on the transmitter I'm reluctant to ditch it just yet

[derelicte]

pulsein is tough?

the multiwii quad guys have the code. you'd just need to find it and bring it over.

[bikerbones1968]

For me using RC TX for control was the way to go. No programming to deal with. Other than channel mixing for thruster. And I love everything about how smooth it works. Bottom line is on only two twisted pair 30awg gives me lighting control, variable speed and multi directional capabilities,pan tilt camera ability, video signal with OSD for sensor data to the surface.

[mikec]

I am not using Arduino. I am only using a RC TX. Signal runs over a single twisted pair comming directly off the DSC/Trainer Port. That signal feeds to the Rc RX that is located on the ROV. No arduino needed! I am not sure if any code has been written to translate PPM/PCM signal to something the Arduino would understand. There are a few guys here using various versions of Arduino that may know programming codes to do this. But if you are using an Arduino why not just use a PS2 controller for control and forget the RC TX and RX. There is already a library for PS2 controllers available for Arduino.

So how does one connect the twisted pair to the RX? I assume it means bypassing the antenna and rf decoding?

[bikerbones1968]

Mikec, any RC transmitter can be used to get the PPM/PCM/SPCM data. You just bypass the RF entirely. Grab the raw data and send it via wire to the receiver. All RX receiver’s use that data to process commands for the hardware. I.e. servos, relays, motors. Just inject the data into the RX and forget the antenna, radio frequencies and RF transmission. This is really easy for any radio that has DSC (Direct Servo Control) You just plug into the DSC port on TX (it shuts off your RF transmit ability) and plug into your RX that is designed for DSC input. Now all controls to the ROV are established. On only one pair. Tested this to 1000 feet, ran out of cable to see if would work further.

[mikec]

Unfortunately my system doesn't have DSC capability, at least as far as I can tell. It does output ppm, which I've been able to read on my sound interface oscilloscope. I've posted a screenshot of that for the interest.

I'm currently using a Futaba TY4F with a R2004GF receiver, but it seems I need to take a different approach and either get hold of an affordable 4ch (or more) rig with DSC or figure out a way of using the PPM from the trainer port. Any suggestions gratefully received!

[bikerbones1968]

Is there a trainer port on that rig? If you have already found the PPM out of the TX then all you need is a RX and locate the PPM input for the ciruit. I will dig around for some information for you.

Having a hard time finding that models manual. Do you have an electronic copy?

[mikec]

I only have the manual for the TX, which does have a trainer port. The ppm signal above was taken from it. Unfortunately I can't find a manual for the RX, so any info you can find would be much appreciated

[bikerbones1968]

Ok thats good you have PPM output established. I will see if I can track down the RX your using and explore where to connect PPM in.

[bikerbones1968]

Hmmm seems this TX is not as easy to hack as the other gear. Still looking into a solution.....