Radio Transmitter for Arduino Uno?

Are there radio transmitters for Arduino Uno that use AM 75.630 MHZ Crystals? I would like to have Arduino Uno control a R/C car.

Not that I'm aware of. You have three alternatives:

  1. Buy an radio system designed for aircraft or more simply, one that has a trainer port on the backside of the controller. With most units, a little internet searching will tell you what the pinout is on the trainer port. You could then put the transmitter in trainer mode and directly feed it a PPM pulse train. This could have the added benefit of giving you extra channels if your receiver has more channels than your transmitter.

  2. Hack apart a standard AM transmitter. Use an O-scope to find where the multiplexer feeds into the transmitter circuit, interrupt that feed and insert a PPM feed from the Arduino.

  3. Use a generic transmitter, feed it a PPM signal and then use another Arduino to decode the PPM signal and send appropriate commands to the various servos.

Also check out: RCArduino: Project Index

I really like this guy's blog and he pops his head in here from time to time. His work with interfacing an Arduino with an RC receiver has paralleled my own work and has been a good sanity check.

My Futaba Attack T2DR R/C transmitter doesn't have trainer port. I don't have O-scope and another Arduino. Any suggestions?

Any suggestions?

When you say you want the Arduino to control the car, where does the radio control come into this? The Arduino would be capable of controlling the servos / speed controllers directly and eliminating the RC transmitter / receiver completely, if you installed it in the car.

My Futaba Attack T2DR R/C transmitter doesn't have trainer port. I don't have O-scope and another Arduino. Any suggestions?

Two possible options:

  1. Take apart the transmitter you have and carefully analyze the circuit board, determining where the multiplexing IC is. (It shouldn't be that hard on an old two channel like your futaba.) Google search the IC's part number and get the data sheet. Determine the pinout from the data sheet and identify the IC's output. This should be your PPM signal. Tap the signal and see if you can decode it with the Arduino and drive a pair of servos to verify the output. Once verified, break that trace and inject the Arduino's PPM signal and see if the receiver will accept the new signal. Keep in mine that Futaba tends to invert their PPM signals.

  2. This is a little more Rube Goldberg: The joy sticks of your remote are connected to 1K or 10K potentiometers that are read by the multiplexing IC and converted to PPM. You could replace the mechanical pots with a digital ones controlled by the Arduino to achieve control of the transmitter's output.

I got the VEX Robotics R/C Transmitter that has a tether port. I don't know who makes the R/C Transmitter. How do I connect the R/C Transmitter to my computer? It has FM 75.61 MHZ Crystals.