
Clearnode digital modes: DMR from an analog radio?
The Clearnode site contains all of the information needed to setup the Clearnode with DMR (and other digital modes) support. I am not going to repeat the Node-Ventures instructions here which essentially mean using the Clearnode mobile app and:
From Connections - choose "add connection" then Click on the tab at the bottom of the "add connection" screen and select DIGITAL.
You can now setup the DMR server name. 3103.repeater.net (for Brandmeister) and tgif.network (for TGIF) are already shown - you need to click on them to enter your DMRID, hotspot security password etc. In my case I changed 3103.repeater.net to 3104.repeater.net, which is the Brandmeister server that I am actually registered with.
Back at the add connections screen, you can now search for talkgroups that you want to add or just enter the talkgroup as TG followed by the talkgroup number (e.g. TG9480) for a group call. For a Private call e.g the Parrot talkgroup, you would enter TG9990# where the trailing # indicates that it is a Private call.
Cool Feature: You can add Brandmeister AND TGIF talkgroups here as you FIRST select the network that you wish to use and THEN select the talkgroup when you are making the DMR connection.
Does it work?
You can now connect to a DMR talkgroup from any analog radio. The clearnode will perform the analog to digital MMDVM conversion via its built in, software DVSWITCH implementation. You select the DMR network and the talkgroup from the mobile app rather than from the radio. My initial attempt worked as the selected talkgroup came up with no problem but apparently my gain was way too high and the returned audio was muddy and had dropouts. I had to make some tweaks to the settings:
Radio settings - Squelch can range from 1 - 8. I used (3)
Radio settings - Volume can range from 1 - 8. I used (5)
The transmit and receive audio was checked via parrot talkgroup to get the best quality.
Final (for now) thoughts
PRO: The DMR settings absolutely worked. The ability to easily use any DMR network and talkgroup was a real plus and one that Pi-Star should adopt, although I'm not sure exactly how Pi-Star would enable this. CON: 1. The audio quality was not as good as when I used a "real" DMR radio with the Pi-star hotspot. 2. The audio quality settings seemed to vary depending on the radio I was using to test (Baofeng BF F8HP and Radioditty GD77 in analog mode)
Note: There is a whole section on the Clearnode site on audio fine tuning and adjusting the audio that I have not yet tried so assume that any "muddiness" in the audio that I mentioned is totally on me as I have not completely tuned the device.