Batboard

I have a Motorola CDM1550 LS model radio. The radio is sitting in my vehicle and I can pick everything up crystal clear. All freq are correct and TPL codes. There is just one problem, it will not let me transmit back. It shows I am talking but no one can hear it or even recieve it. What could be the cause of this?

a little more info. when you try to transmit, does a recieving radio break squelch and lock onto it and just have no audio or does it not even transmit? try a different mic

First thing to do is put a wattmeter on it and verify power output. The PA's in the CDM series are extremely finicky and prone to failure if a bad match or no load is present.

Or if the PA heat sink pad comes loose or is missing.

Depending on the model / band, there might supposed to be a red rubber piece with a button contact attached to it on the top cover inside the radio near the PA. This will not let the radio transmit with the top cover removed. It may be possible that the rubber fell off the last time someone had it apart and didn't know about it or didn't know it fell off.

I am travelling or I would tell you what the models are that have this.