DMR Hotspot using GM340 and MMDVM board

I built this hotspot using surplus PMR mobile, a POG MMDVM card and a raspberry pi.

Thanks to LicesterDMR for the info on how to wire the GM340.

  1. Obtaining a suitable radio.
    I expect many Private Mobile Radios (PMR) could be used but the Motorola GM340 seems most popular probably because it has an external accessory socket which uses standard 0.1 inch pitch pins. At a push you can use individual “dupont wires”. Currently in the UK the VHF GM340 suitable for use on 2m is available on ebay for around £30 plus carriage. The UHF version is harder to find and therefore more expensive.
    I built an interface cable to program the radio as described by M1GEO.
    Program the radio.
  2. Obtain an MMDVM card.
    There are many versions but the one I used is the MMDVM POG board. The circuit diagram and PCB details are available on github. I bought the board ready assembled, with the firmware already loaded complete with 10 pin socket to connect to the radio for £21 from ebay.

3. Configure PiStar

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