SDRTrunk SDRTrunk & R820T - "No tuner channels available"

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Hi all,
Please pardon my newbiness to SDRs and decoding as a whole. Recently I acquired a NooElec NESDR Smart V4 (R820T) to play around with, and so far it's been pretty good decoding pager/ACARS data and just using as a scanner at my desk in general. I then became interested in attempting to listen in to my counties P25 Phase II radio system, and got pretty far in trying to get DSD Plus and SDRTrunk to work.

I created a new channel as followed in a tutorial, went to source, selected Tuner, put in the central frequency for the county, and set the preferred tuner to the R820T. I set up P25 Phase II in the decoder section and enabling the auto-detect system settings option. I proceeded to hit save and start and got the following message:

"Channel could not be started. This is likely because there are no tuner channels available."

The latest message command window that runs alongside the GUI showed this:
"04:33:35.286 INFO i.g.d.d.f.c.PolyphaseChannelManager - Can't provide DDC for Channel:855162500 (855156250-855168750) due to channelizer frequency [1.011E8] and sample rate [2400000.0] [28MB/49MB 59%]".

I researched this message further and found two solutions, either switching USB ports, or going into device manager and setting the SDR up to show as "USB Composite Device". Something possibly worth mentioning here is the fact that my SDR used a tool to change the default drivers in order to set it up. By the way, I am running Windows 10 version 1909.

Afterwards I went to the tuners menu and clicked around a little bit, which then led to another message:

"R820T Tuner Controller - couldn't apply the sample rate setting [2.400 MHz] USB error 9: error writing byte buffer: Pipe error"

I noted that the waterfall is flowing just fine, but after this error message it and sometimes the program just completely freeze after this point.
I also added another channel for my local fire department (UHF, NFM) to test if I get the same results from it, and that was the case.

I'm unsure on how to continue, any help would greatly be appreciated. Thank you.
 

DSheirer

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P25 Phase 2 systems use a Phase 1 control channel. Select the Phase 1 decoder and use the control channel frequency.

Only use the Phase 2 decoder when you want to monitor a phase 2 traffic channel all by itself. The auto-detect feature for Phase 2 only works for a small number of Phase 2 systems that broadcast the WACN and SYSTEM values. Most do not. So, you have to manually enter the WACN, SYSTEM and NAC values in the configuration editor.

You might try plugging the tuner into another USB port. When you get the pipe error, sdrtrunk tries to reset the device, but most times it can't. My airspy has a semi-loose usb connection and everytime I bump it, it does the same.

Denny
 
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P25 Phase 2 systems use a Phase 1 control channel. Select the Phase 1 decoder and use the control channel frequency.

Only use the Phase 2 decoder when you want to monitor a phase 2 traffic channel all by itself. The auto-detect feature for Phase 2 only works for a small number of Phase 2 systems that broadcast the WACN and SYSTEM values. Most do not. So, you have to manually enter the WACN, SYSTEM and NAC values in the configuration editor.

You might try plugging the tuner into another USB port. When you get the pipe error, sdrtrunk tries to reset the device, but most times it can't. My airspy has a semi-loose usb connection and everytime I bump it, it does the same.

Denny
Hello Denny, thank you for replying. I moved the dongle to another port again and this time it started working. However, I've now got a new set of issues trying to compile the JMBE library. When running "gradlew.bat build" it gives the following error:
"Could not initialize class org.codehaus.groovy.runtime.InvokerHelper"

Other than that, the decoder itself appears to be working greatly now.
 

DSheirer

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Use Java JDK 13 to compile JMBE.

JMBE currently uses gradle 6.2 which isn't compatible with JDK 14. I still have to fix this.
 
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Use Java JDK 13 to compile JMBE.

JMBE currently uses gradle 6.2 which isn't compatible with JDK 14. I still have to fix this.
Alright, just got it compiled using JDK 13. I set it up for a control channel and can now see new calls being made. I have set the audio to my default speaks and am hearing nothing. Am I doing anything wrong here?
 

DSheirer

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When you start the application, do you see the line that says that P25 audio will be available? This indicates that the JMBE library was loaded successfully.

Are you seeing the call(s) appear in the audio playback section (next to the speaker icon) or are they just appearing as rows in the Now Playing table?
 
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Log window for P25 audio:

"07:25:28.364 INFO i.g.d.a.c.m.JmbeAudioModule - Loading JMBE library from [C:\Users\Niklaus\Desktop\sdr-trunk-windows-x86_64-v0.4.0\bin\jmbe-1.0.0\build\libs\jmbe.jar] [29MB/45MB 66%]
07:25:28.367 ERROR i.g.d.a.c.m.JmbeAudioModule - Couldn't load JMBE audio conversion library - class not found [29MB/45MB 66%]
07:25:28.367 WARN i.g.d.a.c.m.ImbeAudioModule - JMBE audio conversion library, IMBE CODEC not loaded - P25-1 audio will NOT be available [29MB/45MB 66%]"

I see them as rows in Now Playing.
 
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