DMR on the MD-380

DMR on MMDVM Hotspot

I have been playing with the MMDVM hotspot and the TYT MD-380 for a while.

MD380Tools

Wanted to try the MD380Tools firmware and installed a pre-built binary found here: http://md380.org/releases/daily/
https://github.com/KD4Z/md380tools-vm

Volume bargraph disappears 

First thing to note was the volume bargraph missing. Nothing is displayed when the volume knob is turned. Apparently this is not enabled by default and the firmware has to be built after enabling this option. Will do it in another day. 

Instruction here:

https://github.com/KD4Z/md380tools-vm/raw/master/MD380tools_VM_installation_3.08.pdf

Squelch problem

The new firmware (MD380Tools) seemed to work fine. But there was a problem with the audio muting after a while. Found from the MD380 FB group that there is a tweak to be done to get the "squelch" opening.

Followed this tech note and wrote custom values to the radio.
https://github.com/KD4Z/md380tools-vm/blob/master/Version_5_Hardware_with_MD380tools_firmware.pdf

Fixed BER

Finally the BER reported was slightly high (around 0.3%). Followed this post to get the TX/RX offsets changed.
http://www.k9npx.com/2019/02/hotspot-offset-calibration.html