[MRCA] sincgars question

[W2HX]

Hello all,

Putting the final touches on installing a single radio/long range VRC-90 (I think) in my land rover.  Almost everything is working with one important exception.

I am using the RT-1439, Dual radio mount MT-6352 with RF amp, AM-7239B, Speaker LS-671 (connected to J3 on the base), control monitor C-11291 (J9 on the base) and handset H-250 connected to the LS-671.  The Local/Remote switch on the AM is set to REMOTE.  The LS is able to turn the RT on and off so I believe the local/remote switch is set correctly. The RT is installed in the bottom bay of the AM (Position A)

The problem is when I connect the H-250 to the LS-671, I cannot key the transmitter. It receives fine, but when I key the MIC, nothing happens. If I move the same MIC to the RT itself, it transmits fine and I can hear myself in the LS-671 (is that normal?).

My question is, I wonder if I need a jumper (W4) from the audio out of the RT to the audio connectors on the AM-7239B? Specifically AUD/DATA on the RT to DATA A (J5) on the AM?  Many diagrams show this jumper, but I thought this was to provide audio to the handset when connected to the AUD/DATA on the AM.

Any ideas how to get the radio to transmit when connecting the H-250 to the LS-671? Thanks!

 
73 Eugene W2HX