RE: Why isnt my Futaba working with Jr receiver?
I don't know how a Futaba Tx reacts with a JR crystal in it, but I would not be at all worried if it did not work. If it does not work with a Futaba crystal, then is the time to be worried!
The crystals we use do not vibrate at the frequency of our "channel". They work at much lower frequencies and part of the circuit multiples the crystals vibrations to get to the transmitted frequency. Multiplex uses crystals half the transmitted frequency and actually marks them with the crystal frequency e.g. 17point something Mhz instead of 35point something Mhz. I don't know what JR and Futaba use, but just suppose one uses crystals of 1/2 frequency and the other uses 1/3 frequency, they will never work in each other's Tx. Even if both use the same fraction that doesn't mean they will work. The different circuits may be designed for crystals of different properties, to manipulate the excitation of the crystal and its output.
In other words a JR crystal in a Futaba Tx tells you nothing about whether the Tx is working or not. We use Fut Tx with JR Rx and JR TX with Fut Rx all the time, so it does work.
H