p25 repeater and dsd+

Status
Not open for further replies.

kb9mwr

Member
Joined
Apr 8, 2003
Messages
136
Location
Green Bay, WI
Ryan thanks for your work. I have been looking for a NAC decoder to strobe a serial port for a while.

Ronen, why XP? What we really want is source code so we can have this thing run on a small Raspberry Pi computer.
 

herribe

Member
Joined
Aug 3, 2011
Messages
3
Location
Ponca City, OK
Progress...?

Ryan...

I recently started working in DMR after a friend of mine that is building out a regional DMR system donated one to our amateur radio club. I came across this thread in an effort to see if DSD+ could be used to some way build a simple non-networked repeater for local coverage. Very interesting...

A couple questions though... it's been several months since you've posted anything on this thread, so do you have any updates, or have you put the project aside for awhile?

Also, just wondering if you've tried the most recent version DSD+ (version 1.51 at the moment) with your project? ...looks like 1.51 has been released since your last post here.
 

rjschilder

Member
Premium Subscriber
Joined
Aug 4, 2004
Messages
63
Location
Hales Corners, WI
Hi there,

Sorry, it's been on the proverbial "back burner" for a while now. I kinda gave up on DMR since I don't fully understand the format (nor have I had time to). I do use DSD+ 1.51 currently, but i haven't attempted it with the software I wrote for the repeater. I'll try to dig up the srouce code for the project (i actually had to wipe my laptop a while ago and never dug it out of my backups). Is there something in particular you were looking for?

--Ryan KC9GMY
 
Joined
Jun 16, 2013
Messages
3,379
Location
Texas
Ryan thanks for your work. I have been looking for a NAC decoder to strobe a serial port for a while.

Ronen, why XP? What we really want is source code so we can have this thing run on a small Raspberry Pi computer.
You'd have to rebuild it to work with DSD (not DSD+) as DSD+ at this point in time refuses to support non-Windows based operating systems. DSD+ is closed source, DSD open source. DSD does already run on a Raspberry Pi. It works great with P25, has most of the same options (DSD+ may have been forked from DSD) but TG decoding on DMR is non-existient currently.

Hi there,

Sorry, it's been on the proverbial "back burner" for a while now. I kinda gave up on DMR since I don't fully understand the format (nor have I had time to). I do use DSD+ 1.51 currently, but i haven't attempted it with the software I wrote for the repeater. I'll try to dig up the srouce code for the project (i actually had to wipe my laptop a while ago and never dug it out of my backups). Is there something in particular you were looking for?

--Ryan KC9GMY
A repeater application would be better based off a Linux based application (Linux servers generally have up times measured in years, Windows starts getting flaky after several weeks of up time). If you look at many of the current P25/DMR repeaters out there, they are using a Linux based controller (Simoco is the greatest example of this). Without building a program directly from the standard, DMR is going to be difficult to achieve.

It should be noted, there has been a lot of distortion with testing P25 decoding to analog then encoding to digital again. This is why you don't see P25 repeater built with P25 mobiles like you see with analog. This is why you also see sampling of incoming packets, apply FEC and then either convert to analog (for mixed mode operations, console usage) or just send directly to the exciter. So running discriminator audio to the decoder's sound card and the transmit radio while using serial or GPIO for PTT would provide for the best audio quality.
 
Last edited:
Status
Not open for further replies.
Top