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Just had an old futaba pcm radio and reciever given to me. Very trustworthy guy, he told me it was working when he stopped using it a few years back.

On to the present day..... Transmitter powers up, servos glitch once when the reciver is turned on but there is no communication between reciever and transmitter. Found the transmitter had no crystal in it so i replaced both with a known good set. Still nothing...

Do these radios have any known issues or problems? Any tricks? Can you use them with a normal reciever?

What crystal set did you replace it with?

The radio and reciever were both origonally ch 64 (75.470) and i replaced them both with 75.870. Both crystals are in there proper place. I switched them to be sure and still nothing.

Futaba brand FM crystals?

I run a 3PK with the old 1024pcm Recievers, always work unless a wire failure in the antenna. Look for dirt and or debris inside the reciever case, and check the F plugs and the pins in the reciever- pull the module from the radio and make sure the pins are good too-

If you send me the battery cover, maybe that will help? Lol, I need one for my futaba. is there a multiple vehicle switch on yours? I know on my airtronics radio, there's a switch for up to 3 different cars and the radio won't see the first car if the switch is set to 2 or 3.

I had one that went bad turn out there is a internal crystal that can get damaged if impacted too hard, you can try by hooking it up and slamming the receiver down when the crystal aligns itself it works for a seconds if it does you'll know the damage is there.

On the radio there's a switch from pcm to ppm, switch to ppm any receiver in FM will work in the right freq and channel.

USA-1 wrote:I had one that went bad turn out there is a internal crystal that can get damaged if impacted too hard, you can try by hooking it up and slamming the receiver down when the crystal aligns itself it works for a seconds if it does you'll know the damage is there.

On the radio there's a switch from pcm to ppm, switch to ppm any receiver in FM will work in the right freq and channel.

You don't happen to know where the internal crystal is exactly. Like is it something that can be repaired?

Ok, definately in the reciever. Hooked up a normal one, switched it to ppm and the transmitter works a-ok. Just need to find a pcm reciever now

So the crystals were gold instead of silver?