DSDPlus DSDPlus Simplex Configuration.

[oniell121]

Hey everyone. Longtime unitrunker and SDRTrunk user for trunked systems. I am attempting to monitor SIMPLEX DMR with DSD as a way of learning this software to also use with Simplex NXDN.

I have been unable to get DSDPlus to decode any signals. The audio pipe is working, as I see the waveform of the signal from the VAC in the window. But....nothing.


The old fork of DSD over HERE works just fine with the EXACT same audio setup. I'm piping 52-simplex into a VAC that either version of DSD(+) is piping in. Unfortunately, the fork seems to be no longer maintained, so I was hoping to move over to DSD fastlane, though I have only used Free DSDPlus while I wait for my paypal to be processed and sent the fastlane version information.

Anyway, is this just a PEBKAC error on my part? I've seen threads on here where people are talking about using DSDPlus for simplex, so I'm kinda leaning that direction. But I'm not sure what. Any thoughts?

Setup:
RTL->SDR#->VAC 1->DSDPlus Input

 

[DaveNF2G]

Have you tried using FMP24 for tuning? It cuts out one software hop, removing a potential point of failure.

 

[oniell121]

Hey Dave,

At your suggestion I did a deep dive to figure out all the things in DSD. I only ever used DSDPlus back in the day for Unitrunker and never FMP. So, that was a great way to do this.

For anyone that later looks for this:

I ran into the same problems after using FMP24. After much trial and error, I think my issue was not assigning a role in DSD. For simplex, I used the "-rp" role to assign a passive digital decoder. Of note, this flag isn't in the notes document in the release, but it is visible if you run the help command on the program itself "./DSDPlus -h" in powershell.

For FMP24 I launch with the following flags: This starts FMP24 using my #1 SDR and outputs to FMPx Link of 20001 with a set frequency of 146.520.

.\FMP24 -i1 -o20001 -f'146.52'

For DSDPlus (Using the fastlane release for me). This starts DSD+ as a passive digital decoder with an input link that matches what FMP24 is putting out. This does NOT specify a specific type of digital, thus I was able to test with P25 and DMR from an XTS5000 and SL3500 respectively.

.\DSDPlus -rp -i20001 -o1

 

[mtindor]

Hey Dave,

At your suggestion I did a deep dive to figure out all the things in DSD. I only ever used DSDPlus back in the day for Unitrunker and never FMP. So, that was a great way to do this.

For anyone that later looks for this:

I ran into the same problems after using FMP24. After much trial and error, I think my issue was not assigning a role in DSD. For simplex, I used the "-rp" role to assign a passive digital decoder. Of note, this flag isn't in the notes document in the release, but it is visible if you run the help command on the program itself "./DSDPlus -h" in powershell.

For FMP24 I launch with the following flags: This starts FMP24 using my #1 SDR and outputs to FMPx Link of 20001 with a set frequency of 146.520.

.\FMP24 -i1 -o20001 -f'146.52'

For DSDPlus (Using the fastlane release for me). This starts DSD+ as a passive digital decoder with an input link that matches what FMP24 is putting out. This does NOT specify a specific type of digital, thus I was able to test with P25 and DMR from an XTS5000 and SL3500 respectively.

.\DSDPlus -rp -i20001 -o1

In your original post you were using the original free DSDPlus from years ago. You're using Fast Lane now ? If so, all you have to do is run:

fmp24-cc.bat
1r.bat

Mike

 

[oniell121]

In your original post you were using the original free DSDPlus from years ago. You're using Fast Lane now ? If so, all you have to do is run:

fmp24-cc.bat
1r.bat

Mike

Correct. Don't these launch FMP in control channel mode? Does that even make a difference?

 

[mtindor]

No it doesn't make a difference if it launches in control channel mode. If you tune to a non-trunked freq, it'll just sit there. If it's digital it'll decode it (if it supports the decoding of that digital signal).

If you park on an analog frequency you can even listen to that via the Input menu --> Monitor Source Audio* options.

And, if you did run it with those batch files, decided to park on a control channel and didn't want it to divert to voice calls, you can just use the CTRL menu to select Passive Digital Monitor so that it doesn't bother to check voice, and then use the CTRL menu to select Combined CC/VC Monitor when you want it to trunk track.

 

[seagravebuff60]

Yeah, I suggest using the DSD+ Fast Lane and FMPx, not SDR# piped through something like VAC. It's definitely more simplistic.

Once FMPx is launched, all you need to do is tune to the frequency, and boom, it should decode the DMR signal if it can. DMR simplex or "one Frequency DMR" don't use Control Channels, so I find in DSD+, if it is in CC monitor or combined CC/VC monitor, it doesn't make a difference in voice decoding.

 

[oniell121]

No it doesn't make a difference if it launches in control channel mode. If you tune to a non-trunked freq, it'll just sit there. If it's digital it'll decode it (if it supports the decoding of that digital signal).

If you park on an analog frequency you can even listen to that via the Input menu --> Monitor Source Audio* options.

And, if you did run it with those batch files, decided to park on a control channel and didn't want it to divert to voice calls, you can just use the CTRL menu to select Passive Digital Monitor so that it doesn't bother to check voice, and then use the CTRL menu to select Combined CC/VC Monitor when you want it to trunk track.

Yeah, I suggest using the DSD+ Fast Lane and FMPx, not SDR# piped through something like VAC. It's definitely more simplistic.

Once FMPx is launched, all you need to do is tune to the frequency, and boom, it should decode the DMR signal if it can. DMR simplex or "one Frequency DMR" don't use Control Channels, so I find in DSD+, if it is in CC monitor or combined CC/VC monitor, it doesn't make a difference in voice decoding.

Totally using fastlane from here on out. I'll Test it some more to see if I can pinpoint what was wrong initially and see if I can replicate my issue. As recently as last night, I was having an the same issue with fastlane not getting the audio in, but I suspect that is a configuration issue.

I use SDRTrunk for some DMR conventional channels, but I'll need to use DSD for NXDN that we just went live with.

 

[DaveNF2G]

Totally using fastlane from here on out. I'll Test it some more to see if I can pinpoint what was wrong initially and see if I can replicate my issue. As recently as last night, I was having an the same issue with fastlane not getting the audio in, but I suspect that is a configuration issue.

There is a known issue with DSD occasionally not outputting audio for unknown reasons.