Motorola MX-300 Radio Revival


Model numbers

EPROMS in the MX-300S synthesized radios
When you remove the back cover, the synthesizer unit is at the bottom of the main PCB where the channel elements are normally found on a crystal controlled radio.  There are program once versions of the PROMS and reprogrammable EEPROM versions.  The top of the metal can with the three screws contains the PROM.  The PROMS are numbered either 5096A, 5096B, 5096C, 5096D.  The last letter indicates what type of PROM you are looking at.  

The 5096A and 5096B PROMS are one time fusable link devices and once you program a channel, you are stuck with it. If there are empty channels you can still program them.  

What you really want to find are the EEPROM modules with the part number 5096C and 5096D, these are the reprogrammable EEPROM devices.  You can reprogram them as many times as you like using a Motorola 1801 suitcase radio programming system if you have the right firmware and cables for the programmer.  These programmers go for $1000 to over $2000 on Ebay so most of us don't own them.  

You can find individuals and radio shops who will program your PROMS for a fee.  I suggest you contact John Hansen who offers this service at reasonable rates.
    John Hansen
    (301) 977-2426
    [email protected]

Microphone / accessory connector pinouts

MX Mic Connector

Module numbers by band

Various MX-300 series models

mx gif
MX300S with Scan

mx 300r
Ruggedized MX300R...or is R for "rubberized"

Convertacom mobile dock.