Any JR-compatible module can be used. Here's a list of what I've found to be available:
- Frsky -- $50 for module and one Rx. I've got the older, non-telemetry model.
- Assan X8 -- $85 for module and two Rx
- Corona -- $30 for module and one Rx
- Spektrum DSM2 -- note, this is not DSMX. Available here for about $50
So I don't think any of these are the original module. Anybody know if those are still around?