• Home

  • Forum

  • Participants

  • Contact

  • Blog

  • Archive

  • Search Results

  • More

    A Community of Amateur Radio Enthusiasts

    To see this working, head to your live site.
    1. Participant Forum
    2. New Category
    3. DMR from scratch
    Search
    Kate Stone KD2RYD
    Jul 21, 2020

    DMR from scratch

    To complicate our life’s further and because I like to cook from scratch and because it seems all mmdvm boards are out of stock how about building one from a dev board?


    Ive not looked at the below in detail l, but there must be a way of putting code on a radio dev board, wiring it to an RPi and making your own hotspot.


    https://www.rs-online.com/designspark/building-a-digital-mobile-radio-repeater-part-1-mmdvm

    5 comments
    Paul AC2UQ
    Jul 21, 2020

    Thanks for stimulating our thinking about this issue Kate. Both Neil W2NDG and Chris AC2KV have done this and in the past few days both have offered to conduct Zoom or other video/internet enabled 'meetings' to help others do the same.

    I hope others who read this post will comment so we can understand how many of us would be interested in participating in a 'DMR mmdvm Buildathon'.

    Of course many of us are still focusing on what specifically the mmdvm actually does. What 'goes into it' and 'what comes out of it' and where does the signal go from there?

    Our Friday, July 24th, 9:30 am DMR Zoom Q&A session will seek to ensure that we all have a sufficient understanding to questions such as these.

    About a dozen of us have indicated interest in attending and anyone else who would like to receive an invitation and password can use 'Contact' button at the top of the page to let me know. Thanks again.

    Kate Stone KD2RYD
    Jul 21, 2020

    So, what I’m thinking is a bit beyond program your own hotspot and rpi. I’m thinking of building a radio board mmdvm from radio dev boards, the type the chip supplier provides to prototype with rather than a custom design mmdvm.

    0
    Kate Stone KD2RYD
    Jul 21, 2020

    So, what I’m thinking is a bit beyond program your own hotspot and rpi. I’m thinking of building a radio board mmdvm from radio dev boards, the type the chip supplier provides to prototype with rather than a custom design mmdvm.

    0
    Chris AC2KV
    Jul 22, 2020

    Kate- I like the idea of this but it seems like a lot of work. If the ultimate goal is to build something that will provide a point of access to a DMR network I would definitely go the Pi-Star route. It is open sourced, updated regularly and very stable. If you are looking for high quality MMDVM boards for a RasPi, I can highly recommend the ones sold by N5BOC through his Tindie based store. He designed these boards from the ground up and they are very high quality. They cost a little more than a lot of the Chinese manufactured boards, but they are well worth the money and he does support his products. I own both a duplex and simplex MMDVM board from him using both a Raspberry Pi 3 and a Pi Zero. Both work extremely well. The Pi Zero board has been running continuously for more than a year without issue. From my home I can access the DMR network from almost a quarter mile away without an external antenna, just using the tiny SMA mounted rubber duck.

    Chris AC2KV
    Jul 22, 2020

    Forgot to post a link to the N5BOC Tindie store.


    https://www.tindie.com/stores/n5boc/