Using the Motorola Maxtrac/GM300 on echolink

To do our echolink operations, we decided to use the VA3TO interface.

Details can be found here.



We designed a small module to interface between our radio of choice, the Motorola Maxtrac or GM300. These radios are reliable, very durable and easily adaptable to a variety of situations. All of our references on these pages require a radio with the expanded signaling board. That would be radios with 16 or 32 channels, and a 16 pin connector on the back that is programmable. A 2 or 8 channel radio, or a radio with a 5 pin connector will not work with this setup. CDM series radios will also work just fine. All connections are via the rear connector.
This is the module designed by David Latta, KG4SNN. It is to interface the VA3TO interface above to the Maxtrac radio. It is connected to the rear of the VA3TO interface and the computer sound card with an assortment of patch cables. (See below)





This is the 16 pin connector on the KG4SNN module that would connect to the Motorola radio.



This is an internal view of the KG4SNN module.



So what else do you need to get setup? Well, a computer running a decent version of windows, the echolink software, and patch cables to make your connections. You will also need a serial cable to connect the VA3TO interface to a COM port on your computer (this keys your radio).

Want to see the wiring diagrams and additional notes? Here is a short powerpoint with the details. Get in touch with us if you have any questions.