SDRTrunk SDRTrunk Directed Audio Output

axmeone

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I have been scanning with traditional radios for a few years but picked up a couple of RTL-SDRs over this past weekend. I've been able to get SDRTrunk up and running on my local P25 simulcast system. I have it configured to decode only two specific talk groups and intentionally mute all others.

I was hoping for some ideas on how best to direct each TG's audio to a dedicated audio device (called Sound playback device in Windows).

Similar to this USB audio adapter:
1674614079298.png

I don't see an option which provides that level of granularity in SDRTrunk.

Has anyone done something like this?
 

belvdr

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I am not aware of for to do that in SDRtrunk. An audio mixer should do this, but may be pricey for the features you need.
 

GTR8000

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Not possible currently. All audio from SDRTrunk outputs to the same device or virtual cable, either in mono or stereo, but there is no provision for selecting a device per-talkgroup.

As for the mixer idea, I don't see how that's going to make any difference given the above.
 

belvdr

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Not possible currently. All audio from SDRTrunk outputs to the same device or virtual cable, either in mono or stereo, but there is no provision for selecting a device per-talkgroup.

As for the mixer idea, I don't see how that's going to make any difference given the above.
I think some USB mixers will allow you to direct audio where you want.
 

axmeone

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Not possible currently. All audio from SDRTrunk outputs to the same device or virtual cable, either in mono or stereo, but there is no provision for selecting a device per-talkgroup.

As for the mixer idea, I don't see how that's going to make any difference given the above.
Sounds like the answer I was fearing.

Smells like an SDRTrunk feature request ;)
 

GTR8000

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I think some USB mixers will allow you to direct audio where you want.
Sure, but when the software is only able to output to a single device...how is a mixer going to help? He wants to select an output device per-talkgroup, which the software is not capable of doing currently. I don't see any sort of mixer being able to "intercept" the decoded audio from SDRTrunk in order to direct it to a specific output device.
 

belvdr

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Sure, but when the software is only able to output to a single device...how is a mixer going to help? He wants to select an output device per-talkgroup, which the software is not capable of doing currently. I don't see any sort of mixer being able to "intercept" the decoded audio from SDRTrunk in order to direct it to a specific output device.
I wasn't thinking correctly. You're right.
 

axmeone

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Good question... My plan is to replicate what I currently have with my dedicated scanners. Each scanner is configured to decode 1 TG and pipes its audio via a physical but transformer isolated audio cable into a dedicated audio adapter on another PC running my BlueIris NVR. In addition to my traditional camera profiles, I also have several "audio only" BlueIris camera profiles which record based on audio level triggers. This allows me to (per TG) stream live or go back and listen to history from anywhere via BlueIris.

Ideally, I would like to have SDRTrunk or equivalent running on one PC then have it send each TG to the BlueIris PC via TG dedicated audio cables.

I know there are generally many ways to skin a cat but this method has been working great for years.
 

scannerbox

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One way that might be able to do what you are asking for is with adding Trunking Recorder if you are using Windows.
You would setup SDRTrunk to record the calls and then Trunking Recorder would import the audio files once the call is over.
Trunking Recorder can then be setup to play selected talkgroups to specific audio devices on the computer using the "streaming" feature.
This would add a slight delay since the audio wouldn't start until the call is over in SDRTrunk.

Also, Trunking Recorder provides a web interface that allows you to search and play back all record calls. You are able to see all the call MetaData so it makes finding calls easy.

What a lot of people do is setup SDRTrunk to record all/most talkgroups on the system and have them imported into Trunking Recorder.
Then you choose which talkgroups you want played back through each stream. Trunking Recorder can also queue up calls so if two calls happen at the same time from different talkgroups you won't miss any activity. This does add a few seconds of delay so if you really need real-time playback like a scanner it could be an issue. (Most people don't really need real-time playback.)

For more info on Trunking Recorder take a look at Trunking Recorder - Recording audio from trunked radio systems monitored by Unitrunker and SDRTrunk
 

axmeone

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Thanks for your suggestion. I appreciate the time it took you. One of my goals here too is to keep things as simple (CPU friendly) as possible. I don't have a need for meta data since I only listen to a couple of TGs. Your suggestion sounds feasible but not as attractive as simply redirecting right at the source, from a new field per talk group for instance. I know I'm probably over trivializing the effort to implement something like this but it can't hurt to ask.

Again, thank you for your ideas.
 

abqscan

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Trunking Recorder puts nearly zero strain on the cpu. Think of Trunking Recorder as Blue Iris specificly built for SDRTrunk. It is literally operates like an NVR. If will provide you what you want from where ever you are just like Blue Iris. You can listen live or go back to as long as you have the program set to record for. You can access your audio from any smart phone or computer conntected to the internet.
 

axmeone

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All I can say is wow! As time goes on, I am realizing even more how awesome Trunking Recorder targets my needs.

Is there an option to run it as a service in Windows?
 
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