There are a lot of different transmitter / receivers available from any Manufacturer.
In the case of JR some transmitters won't transmit in the PCM mode (basic radios) so not all transmitters / receivers will work together. I would suggest sending the items in for a check up in any case (I use JR service center as they have the parts needed just in case).
Member dsnyder here at RC Universe in the following fourm is the best contact for JR information.
> Radio Manufacturer Support Sub-Forum > JR Radios - Ask Danny at JR
http://www.rcuniverse.com/forumdispl...s=&forumid=174
EXCAP232