Batboard

I need to replace a UHF Radius mobile power amp and heat sink. Are all M100, M120, M130, and GM300 amps the same if frequency range and power level match? Can a 40 watt amp be replaced with a 25 watt amp?

MaxTrac and Radius PAs ARE identical as far as the radio is concerned. GM300s have a temp sensor on the PA and a 6-pin connector for the logic board that's incompatible with the 5-pin connectors and cables on MaxTrac and Radius products. I don't think you can mix-and-match GM300 and MaxTrac/Radius assemblies like that.

If you swap PAs, you'll need to realign the output power settings, probably following the logic board replacement procedure too. It would also help if you relabeled the radio so the next owner realizes it's no longer capable of 45 watts.

Bob M.

Gone

I'm sure you could put a GM300 PA onto a MaxTrac or Radius, knowing that the connector to the logic board is a 6-pin plug trying to fit into a 5-pin socket. In theory, the major difference is the temp sensing components on the GM300 PA.

However, I'd go buy another used MaxTrac/Radius first.

Bob M.

On the maxtrac 5 pin connector,you can cut away the plastic,and the 6 pin gm 300 pa will plug in and work fine.
mod

n5tbu wrote:On the maxtrac 5 pin connector,you can cut away the plastic,and the 6 pin gm 300 pa will plug in and work fine.
mod

I have done the same, cut one end of the plug housing on the logic board.

I had several GM300/M120 UHF 40 watt PAs that were brand new, and put them on Radius M100/M216 radios without any problems. BUT you have to do the Power Amp board replacement alignment in the Service section of the RSS. This sets the power output accross the freq range.