Another SDRTrunk no audio.

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humblegeo

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SDRSharp audio works fine. SDRTrunk no audio. Do I need a second sdr dongle for the audio part to work on SDRTrunk? I will probably be ordering 2 new RTL-SDR V3 dongles in the future but for now I am just playing around with what I've got RTL 2832 SDR/R820T and was trying to learn SDRTrunk. Watched several youtube videos to help with the setup Nate the Robot. Everything seems to be up and running except no audio. I have radioreference premium so It was easy enough to setup the system, site, talkgroup, control channel etc etc. I am somewhat familiar with the process from experience programming Radio Shack PRO-668 and Whistler WS-1080 scanners using radioreference frequency database. Simuliar process. Under User Preferences, Output tones: Audio Output Device, Primary Sound Driver-Mono. When I do the TEST I get a beep out of my Dell built-in computer speakers. Windows 10. Under Decoder, JMBE Audio Library, Current Version 1.0.7b, I did the Check For Library Update and it went thru the process, creating a new JMBE Library and showing path. What did I miss or is a second sdr dongle required? P25 phase 1 and 2. Trunking system simulcast.

I wonder if under the streaming tab where it says: (click the NEW button to create a new audio streaming configuration). I haven't done anything with this yet and I don't know if maybe it's not required for the basic operation to work??

Appreciate advice
LG
 
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lwvmobile

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Have you tried just setting up a NOAA weather radio NBFM channel? Its a good way to test whether or not you are getting any audio out, or if something else is going on. You can also just go into preferences and try the test beeps to see if you hear anything at all. Also, which system are you using SDRTrunk to monitor? You will need more than one dongle IF the entire system you want to monitor is greater than the bandwidth that is usable on an RTL dongle, which is usually 2.048 to 2.4 Mhz (Msps).

Another thing to try if you think you should be getting some audio, but not all audio, is to manually enter the system CC in a new channel with the appropriate system type. Remember seeing a few people reporting that the RR import may or may not work properly for P1 and P2 type systems for some reason, but manually setting it up worked fine for them. Also, toggling between LSM in the channel settings may do the trick if one or the other isn't working. I believe LSM is for Simulcast, if memory serves. Don't have SDRTrunk open at the moment to verify.
 

DS506

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Is anything else using the one dongle? If you have SDR# using it and you open SDRTrunk, SDRTrunk will not have a tuner to use. Turn off both, disconnect and reconnect the dongle. Restart SDRTrunk.
There may be a way to tell SDRTrunk that there are new tuners to use without restarting the software, but I do not know how.
Have you tried just setting up a NOAA weather radio NBFM channel?
The easiest way to test is with a single frequency without any special decoding. Create a new NBFM playlist with your strongest NOAA station as the only frequency. Play that channel. If that works, your basic audio works.
With just the frequencies showing in your screen shot, you would need multiple dongles to fully monitor that system. Each RTL-SDR dongle can tune a 2MHz range. So one might cover roughly 171-173, 2nd 173-175, 3rd 850-852 MHz
 

n0gik

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What is the sample rate on your tuner set for? If it is too narrow to fit the system frequencies it will look for another dongle to do the work, if none located you get error tuner unavailable. Try 2.048 or higher if your SDR will support it. Good luck.
 

humblegeo

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What is the sample rate on your tuner set for? If it is too narrow to fit the system frequencies it will look for another dongle to do the work, if none located you get error tuner unavailable. Try 2.048 or higher if your SDR will support it. Good luck.
From what I can find on the tuner for a RTL2832U and R820T is that it can tune into signals from 24MHz to 1850MHz. I originally had the sample rate set at 2.400 MHz but I've tried all the choices still no sound. When you go to the NOW PLAYING tab and then the EVENTS tab looking under the details columns all the messages are streaming by very quickly (wish I could hit pause and be able to read them) but I can see TUNER UNAVAILABLE-PHASE 1 GRANT and TUNER UNAVAILABLE-PHASE 1 GRANT PR14 CIRCUIT and TUNER UNAVAILABLE-PHASE 1 GRANT NSAP 1:1 CIRCUIT. I think I will try and setup a NOA Weather station and see if I get sound. If a person were to add another tuner, how would you do that? appreciate it. Just trying to learn this SDRTrunk

I probably need a second dongle and then figure out how to set that up in SDRTrunk . The frequency range of the system I'm trying to monitor may be spread out further than what a single dongle can cover (2.4 MHz of bandwidth)??
 
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humblegeo

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Just purchased two RTL-SDR Blog V3 RTL2832 1PPM TCXO HF BiasT SMA Software Defined Radios. One is just the dongle itself to replace my existing RTL-2832 R820T which already has a cable and antenna setup and the other has all this stuff with it. Only problem is they come from China and takes over a month to get here. I made sure to purchase thru "rtl-sdr-blog" the official eBay account for RTL-SDR Blog and paid thru paypal. So I've got over a month to learn SDRTrunk or others like DSDPlus.

  • 1x Dipole antenna base with 60cm RG174
  • 2x 23cm to 1m telescopic antenna
  • 2x 5cm to 13cm telescopic antenna
  • 1x 3m RG174 extension cable
  • 1x Flexible tripod mount
  • 1x Suction cup mount
 

mk262

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You've got a couple different symptoms of the same problem. The tuner can only theoretically and simultaneously get about 2.4mhz of bandwidth. That's a 2.4mhz window into whatever you want to follow. Meaning ideally you want to have all relevant channels including the control channel inside that window all the time.

I think you're listening to the Harris County NE Simulcast system. It includes:

770.23125
771.23125
771.98125
773.21875
774.15625
774.43125
(4.2mhz span)

851.450
851.600
852.5875
852.925
853.125
854.0875
(2.64mhz span)

As you can see, 2.4mhz of bandwidth cannot cover all of the 700mhz channels OR 800mhz channels and certainly not both at the same time. You'll need four dongles to cover the entire thing.

What's happening today is, sdrtrunk doesn't want to tune away and lose the control channel and go pick up a single audio channel (how a scanner works). This is why it won't record the audio, it can't.

Epilogue: You're in a busy metro area with a lot to monitor. Depending on what you what to listen to and how powerful of a PC you're working with, you might be better served with a couple airspy r2 (10mhz) or a hackrf (20mhz). To know precisely how useful that would be to you would involve knowing all possible frequencies you want to deal with and how close they are arranged.

I'd also recommend setting an appropriate recordings folder in your sdrtrunk settings and using the trunking recorder app (google it) to manage all that recording for you.

Hope this helps.
 
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mk262

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Yes Texas Wide Area Radio Network (TxWARN) which is a P25 Phase 2 system. site 13: Harris County Northeast Simulcast and only talkgroups Harris County Constable Precinct 4 dispatch 00711, 00713, 00715, 00717.
That's it.

Copy. Unfortunately the number of talkgroups being small won't help. When a user keys up, that talkgroup is going to be assigned the next available voice frequency (that's actually an oversimplification...) so you'll have to cover the entire TRS in bandwidth to always get it.
 

humblegeo

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Copy. Unfortunately the number of talkgroups being small won't help. When a user keys up, that talkgroup is going to be assigned the next available voice frequency (that's actually an oversimplification...) so you'll have to cover the entire TRS in bandwidth to always get it.
Appreciate the education mk262. Now I wish I hadn't ordered today the 2 RTL-SDR V3 dongles. Bandwidth maybe 5 pushing 6 MHz together. Would have been better to spend more like $100 on a airspy r2 dongle that covers 6MHz with one dongle. Guess I would need 2...$200+. Oh well, too late now. I might try the one dongle I have with this site.

1 (1)038 (26)HuffmanHarris851.375851.9375852.4625853.0375a853.975c
 
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mk262

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Appreciate the education mk262. Now I wish I hadn't ordered today the 2 RTL-SDR V3 dongles. Bandwidth maybe 5 pushing 6 MHz together. Would have been better to spend more like $100 on a airspy r2 dongle that covers 6MHz with one dongle. Oh well, too late now. I might try the one dongle I have with this site.

1 (1)038 (26)HuffmanHarris851.375851.9375852.4625853.0375a853.975c

Yeah it's one of those things that takes a minute to get your arms around.

One dongle would be able to cover most of that system at least.
 

DS506

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As far as setting up multiple dongles in SDRTrunk; plug and play.
Plug all the dongles into the computer then start SDRTrunk. It finds the dongles. In the Playlist Editor, Channels. Select the system you want to monitor and click play.

NOTE; You might need a USB hub to plug the dongles into. As the USB end of the dongle is larger than the typical cable, you might need USB extension cables to give you room to work.
 

humblegeo

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It is working now with the site I selected with a smaller bandwidth. 2.6 MHz between highest frequency and lowest frequency. At least I'm getting pretty clear audio now.
 

maus92

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4 rtl-sdr type dongles will use less system resources than 2 airspy or 2 hackrf devices that would be needed to cover the op's requirements.
 
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