Can a person use moto mic's on all their radios by rewiring the end plugs I have a few mic's and want to change the plugs to work on my Gn300's and Maxtracs and how to do this re Colors and positions of wires in a cat6 plug
There's a couple of things that have to happen to make mics work on a radio. Obviously, correct pin out is important. Also, the impedance has to be matched or you won't get good audio out of it, but the mic gain on the radio might cover that, and if not, it's not hard to match it externally. Lastly, some mics need phantom power and some don't.
That last one is the killer -- if your radio is unable to supply or suppress the phantom power for a mic that needs or can't use it, you won't be able to use the mic on the radio without some external conversion circuitry.
Beyond that, the hard part of getting it to work is finding the correct mic plug that fits the radio, finding the pin out for the radio.
Older Motorola two way radios and microphones used a relatively standardized interface.
The connections to them are generally:
GND - ground
PTT - the PTT switch connects this to ground to key radio
MIC HI - microphone audio. The radio supplies a bias voltage (around 9V) to this pin to power an amplifier in the mic and in some, an electronic PTT switch.
HOOK - connects to ground through hang-up contact on rear of mic to put radio in monitor mode when the mic is taken out of it's holder.
You can find the wiring diagrams for various radios and mics online (try www.batlabs.com), and in most cases just matching up these connections will get a Moto radio to work with a Moto mic.
One thing to note on the 8 pin modular connectors is that Motorola reverses the pin numbers in their diagrams from what you would usually see for an "RJ-45" plug. So what's normally pin 1, Moto calls pin 8, 2 is 7, 3 is 6, etc., this trips a lot of people up.
My radio (mcHF) is a kit and didn't come with a microphone, so I had to match one up. I learnt that the biggest issue is whether the radio requires a dynamic microphone or an electret microphone (aka condenser). A radio is designed for one or the other.
Beyond that there are other differences, but the instructions to my kit imply that I don't need to worry about those differences. For example, the dynamic mics come in different impedances, but no one seems to worry about this when matching a mic to the mcHF radio. Maybe most mics come in an impedance range that the radio can tolerate.
Disclaimer: I am a newbie and just sharing my limited experience.