How to test 2 way radios?

Im new to this forum and to 2 way radios. I just bought a lot of 19 radios at an auction and would like to test them but don’t know how to get power to them or what else I should test. There are mainly 3 different models of radios I got. Motorola MaxTrac, Motorola CM300, Motorola SM50. All came with the handheld mics too. Any advice on how to test & clean them up would be great.

                                            Thanks Drew

HI Drew,

Since you’re new to 2-way radio, I’m assuming you’re not well versed with general electronics as well. How easy this is will depend on what you know or don’t know. Here’s a few questions to get me an idea of where you’re at. Do the radios have 1. Antennas 2.Batteries 3. What kind of batteries? 4. Chargers? 5.Frequency Limits Can you use a multi-meter? Get back to me and I’ll see if I can help you.


Because you are not licensed to operate on the frequencies that those radios are designed for, you need to test them into a dummy load and with a service monitor.

This is the reason why you pay a two way shop to do your radio work for you. It would be illegal to transmit, even just a dead carrier on a public service frequency with a radio and a antenna.
Each of those radios would need to be reprogrammed to a legal frequency for you to operate them.
The Motorola’s might require a RIB and a Motorola computer program to program them.

Peter- I have a good working knowledge on electronics, Just not 2-way radios. I’m really just looking to see if they power up so I can sell them. If I can legally test them more that would be great. I added a few pics of the radios I have.

If you have the wiring harness, you connect the RED to the Positive terminal of a 13.8 VDC power supply or automotive battery.
Push the button on the Motorola MaxTrax / GM 300 and it should turn on.

It needs to be connected to a Motorola sleeve - Astron Power supply or the original harness.

Here is a link for more information -

The only people you could sell them to would be someone in public service, because if it was used for amateur radio, it would probably burn up in short order because it is not a duty rated radio.

Unless you have the software and the license, you can’t program it.

SM 50 is just a two channel radio - kind of hard to sell to anyone these days when you can get a lot better radio for a couple of dollars more.
It was a CHEAP radio that doesn’t do anything especially well.