| Thanks for the URL leads on what is available. You guessed it in your
| last paragraph. I am looking for a way to possibly "piggyback" (or
| modulate) a subchannel onto an existing RC channel... ideally with
| minimum modifications to both the receiver and transmitter. An
| alternative might be to just develop a receiver/transmitter pair on a
| separate public use RF band, sort of a separate telemetry channel.
| Still thinking further out of the box, making the channel two way would
| allow commands to be sent and results to be transmitted back.
Well, the list of things you described can all be done with the sort
of thing I described and no changes made to your TX at all. The only
limitation is that you'd have to use one channel for each item or each
For example, if you have a three position switch, that will send a
signal of either 1.0 ms, 1.5 ms or 2.0 ms. So you can have 1.5 ms do
nothing, 1.0 ms toggle the lights and 2.0 ms take a picture. Or if
you have a two position switch, 1.0 ms = lights on, 2.0 ms = lights
off. Landing gears are often done with retract servos that are all or
nothing -- they're not porportional at all.
You could also do this on an unused stick -- middle do nothing, up do
one thing, down do another way.
With a few channels dedicated to this, you could do all the things
you've described. But yes, it sounds like what you want might be
easiest done with a completely seperate RF link. Do take lots of care
to make sure any TX in your plane doesn't desense the 72 MHz RX!
| > | I understand that there may be receiver/transmitter pairs available
| > | which would allow a user to send custom command information to the
| > | receiver. Conceivably a small microprocessor onboard the aircraft would
| > | be able to decipher these commands and carry out special functions
| > | (turn on/off lights, landing gears up/down, trigger small digital
| > | cameras, deploy parachutes, etc.)
Doug McLaren, email@example.com
"I'd rather be lucky than good, any day" --well known auto-racing saying
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