SDRTrunk and Raspberry 5 Audio issue

[will40]

Hi I hope some of you can help me. So I have been running OP25 on a Rpi4 for about 6 months to pick up my local P25 PH1 digital police and fire channels. It works well except that it doesn't capture all of the responses.

I installed SDRTrunk on a Windows PC and found that it worked much better. It seemed to never miss a transmission from either police or fire.

In an effort to condense the hardware I purchased an Rpi5 8GB board. Installed Pi OS 64 bit desktop. Installed the most recent SDRTrunk 0.6.0 added my two local P25 freqs, no alias's, single tuner, and she started running.

Transmissions came right in very clear from both freqs. But unfortunately the audio output stopped after a few minutes. The event log continues to reflect the transmissions but no output of audio to my speaker.

If I restart the Pi all is well again but typical audio issue from the SDRTrunk ceases but still logging the transmissions.

In an effort to test my Rpi5 audio output while SDRTrunk was running, I opened VLC and played an MP3 file with no problem. I even went and played a youtube video and the audio outputs fine. The SDRTrunk is still capturing the freqs and logging them. CPU is at 50% and memory is at 1.5G.

I went and added alias with talk group ID range and that works as well. I can listen and record both freqs. The recordings also continue after the SDRT audio ceases.

Does anybody have a recommendation to what I can check next?

Thanks for any help.

 

[maus92]

Rasberry Pi is not an ideal hardware platform for this software. I suggest a used / refurbished micro PC from Dell, HP or Lenovo. They are slightly more expensive than RP but more powerful and stable.

 

[will40]

ok, thanks for sharing that

 

[boatbod]

I have been running OP25 on a Rpi4 for about 6 months to pick up my local P25 PH1 digital police and fire channels. It works well except that it doesn't capture all of the responses.

I'd be curious to hear more about that. Are you saying it is not seeing the channel grants when it's not doing anything else, or that it misses transmissions because it's already decoding another call?

 

[will40]

I am not sure what causes it. It seems to be short transmissions such as quick 1-2 second acknowledgements. I have two frequencies in the truck.tsv so perhaps it is scanning the other freq when this happens?

I tossed out my original SDRTrunk idea for the Rpi5 and just finished installing OP25 on it. So far so good as I am comparing to the Rpi4 running OP25. Seems the Rpi5 decodes a little faster.

BTW great package. Overall I am very pleased with its performance!

Are their any plans to add a channel record feature in the near future? I am interested in taking an MP3 or Wav file and converting to text for a hearing impaired family member.

 

[boatbod]

Possibly this is an artifact of the rather slow demodulator time to lock a new signal when tuning. Often the HDU or MAC_PTT gets lost and this can cause a small delay in starting voice decode. Mostly not noticable, except on really short transmissions.

Sorry, I don't have any immediate plans for recording functionality. Too many other time commitments in my life right now!

 

[will40]

Sorry, I don't have any immediate plans for recording functionality. Too many other time commitments in my life right now!

No problem. I understand completely!