DMR, Pi-Star hotspot - lots to learn

[delta_charlie]

Hi all, curious if anyone on the forum has been messing around with DMR and the Pi-star hotspot?

One of my hobbies is I love messing around with the Raspberry Pi and when I recently learned that a DMR hotspot can be setup on the Pi zero using Pi-star software and an inexpensive MMDVM hat that goes on top of the Pi zero I just had to give it a go. Was able to get it put together and running the Pi-star. Now working on the configuration and trying to learn how it is setup. Have not been active in ham radio for a while but I did renew back in 2017. Had a little bit of a delay getting my login to the ULS sorted out so I could fetch the required original amateur radio license. Just got it this morning so I should have my DMR number soon. Hopefully I'll have it working in a bit and can enjoy a little amateur radio.

Below is a picture of the little pi zero hotspot, that's a standard USB plug on the left for scale.

 

[delta_charlie]

Here is what the control panel for the pi-star running on the Raspberry Pi zero looks like. Think I have it ready to go. Just waiting on my new DMR HT to come in.

 

[Titanium]

I have several MMDVM based hotspot hats running on Pi Zero's and also installed a few OpenSpots in the vault with the C4FM repeater. Use as YSF nodes for our club FCS room Sierra NorCal - FCS00360 and Youtubers - FCS00348. Really handy devices to connect repeaters and also when no direct RF path is available.

Just ordered an Openspot3 to be able to transcode between Fusion/DMR/Dstar.

 

[delta_charlie]

I have several MMDVM based hotspot hats running on Pi Zero's and also installed a few OpenSpots in the vault with the C4FM repeater. Use as YSF nodes for our club FCS room Sierra NorCal - FCS00360 and Youtubers - FCS00348. Really handy devices to connect repeaters and also when no direct RF path is available.

Just ordered an Openspot3 to be able to transcode between Fusion/DMR/Dstar.

I never really had much success hitting any of the local repeaters using a HT. That's part of what caught my interesting in setting up the hotspot. Would really like to be able to walk around the back yard with the HT and not have to be tied to the base running 20 watts or so just to use the local repeater.

Getting things working with the new DMR HT does seem to have a huge learning curve but I'm making progress Been running some parrot tests and things are looking mostly good. Was using GQRX to monitor the signal trying to see if I might need any offset but the BER looks good and both the HT and the hotspot look to be lined up well but what's up with the messy output from the HT? I do have it on low and the receiver (SDR) is outside 50 feet or so.

The lower part of the waterfall display is the HT and the upper is the reply from the hotspot.

Is it just swamping the SDR or do I need to investigate some more? Thanks, Dale