RE: Tx Rx crystal/freq mystery
Does Futaba make a 4-channel FM system?
I believe the 3 and 4 channel systems are AM, and the crystals are incompatible with FM.
I have several 6 channel Futaba FM systems, but can't recall seeing a 5 or fewer on FM.
Hitec does only FM stuff. But some of their crystals won't swap between model series.