Where are you changing crystals? in the RX or the TX module?

You can not legally change crystals in the TX module.

The TX modules DO use different crystals from the ones used in TX's that don't have the modules.

The same module that fits a Futaba FG series FM radio (which is not PCM capable) fits my Futaba Super-7 which is PCM. PCM or PPM has nothing to do with RF tuning.

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Still interpreting your posts...


Which reciever did you buy? (Make and model number) Which crystal are you sticking in? (list the make and model RX it was pulled from.)