SDRTrunk making me so mad I could scream

[Indianabrad]

I am so mad it is truly hard for me to write this post without cussing.

The setup: 1. Nooelec NESDR SMArt v4.
2. SDRTrunk setup & configed for Phase 1 & 2 and RR talkgroup IDs imported into the program.

I am using SDRTrunk ver. 0.5.0 and every time that SDRTrunk picks up a comm it will play the audio of it for about 3 seconds then in the "Event column" it will then show "Group Call - Rejected" and stop playing the audio. It does this on EVERY comm it receives and sometimes it will show "Patch Call - Rejected". I have turned off, in the setting, everything related to "Duplicate Calls", but this piece of "%&$#*!" just keeps rejecting all the comms. SDRTrunk also shows the comm still in progress in the columns area, although it refuses to play it. I also have a real scanner that continues to play the comm in its entity, so I know how long the comm lasts & how much SDRTrunk is refusing to play of the comm.

All of this makes me so mad I could cuss out load a blue streak.

 

[n0esc]

How wide is the frequency spread of your control channel and all possible transmit frequencies? It's likely that a single dongle doesn't have enough bandwidth to cover the whole system. SDRTrunk is designed to home on the CC and is probably dumping once calls are showing up outside of the available spectrum. Adding extra dongles is probably the way to go. I needed 3 to cover the system I am monitoring just due to how far apart the frequencies are on the local system. Here is a thread covering what you are probably experiencing: Missing Some Traffic Because Control Channel Is Locked

 

[Indianabrad]

How wide is the frequency spread of your control channel and all possible transmit frequencies?

There is no prob receiving the CC, this is not a reception prob, the data in the "message box" flows like wine at a millions scrolls per minute.

 

[n0esc]

Understood. SDRTrunk will sit on the CC frequency by design. The issue is that all NESDR dongles only have about a 3MHz bandwidth. Looking at a system associated with your area, there are control channels on 859 and ~855, as well as TX on 851-853. Even if you ignore the 859 CC, and hope or know it isn't important, there is too wide of a spread to reliably cover the entire system. My suspicion is that anytime the CC is indicating a TX on the 851 channel, that's where your error is cropping up. You'll need at least one more dongle to cover 851-855 fully, and something like a pair of Airspy Minis or an AirspyR2 with a larger bandwidth than the NESDR based dongles to cover the full range of 851-859.

 

[boatbod]

Might I suggest if you are really that angry at the behavior of free software you didn't pay a nickle for, try one of the others. There are at least two mainstream apps I know about which are capable of trunk-tracking a P25 system using a single dongle.

 

[Indianabrad]

There are at least two mainstream apps I know about which are capable of trunk-tracking a P25 system using a single dongle

Care to say what they are?

 

[Indianabrad]

Understood. SDRTrunk will sit on the CC frequency by design.

There are two P25 "First Responder" sites in my county, they are about 25 miles apart. I am in between them and about 1/3 closer to one of them. One site has a CC freq of 859.9625 and the other site has a CC freq of 859.9375. I receive both of them really well on my real scanners & I have the same kind of antenna on the SDR. Both sites have channels down to 851 MHz, so are you saying that only one tuner doesn't have enough bandwidth to go down there from where the CC is? Also I do have both sites on 1 tuner. ... So are you saying that if I got another tuner & gave each site a tuner, it would work better?

 

[Indianabrad]

My suspicion is that anytime the CC is indicating a TX on the 851 channel, that's where your error is cropping up.

I also noticed that when it stops playing the comm, in the "details" box it says "Tuner unavailable - Phase 1 Channel Grant". Is this related to what you are talking about of a lack of bandwidth?

 

[donslade]

I am using SDRTrunk 0.5 Release 6. The system I monitor has has a 6.1875MHz spread (854..0125 to 860.2). I used two SDRs since they typically have about 2.7MHz bandwidth and have no problem monitoring all comms in this system. I am currently monitoring only 1 system.

The "Tuner unavailable" error is an indicator that your one SDR does not have the bandwidth to get to that channel and no other tuner is available to tune it.

I am currently using a HackRF One clone that works great but I was using an RTL-SDR and a Nooelec NESDR Smart V3 together also working great.

 

[dave3825]

Maybe if you can post a link to the system and indicate what sites on that system your in range of, we can help. I run a nooelec on a system whose spread is 2.4375 mhz and I set the sample rate for 2.56 and she runs. I have other systems that are larger so I either add more dongles or run my airspy. I have run 3 different systems with the airspy mini running at 6.00 and 2 more systems running 2 nooelecs at 2.56.

OP25 (Boadbod version) rocks and does phase 1 and 2 and that's what I use on my Pi. Unitrunker is good but does not do phase 2 and dsdplus works good for phase 2 also.

it says "Tuner unavailable - Phase 1 Channel Grant". Is this related to what you are talking about of a lack of bandwidth?

Yes. The channel that the voice comm is on is too for from the control channel. . Can you post the system and sites in range? There might be on that will work for you.

 

[Indianabrad]

You'll need at least one more dongle to cover 851-855 fully

After reading another post on here about a guy having the "Tuner unavailable " prob, I was able to turn up the sample rate on my SDR to 2.8 MHz. .... Also, in SDRTrunk do you just use the site CC channel like a reg scanner? I "remade" my channels & clicked on "include all channesl" and now I can see all of the site channels being scanned through, in the main view of SDRTrunk. Is this wrong or right?

 

[donslade]

I have also used OP25 and it really cooks with just one RTL-SDR or NESDR. I have a RPi 3B+ using an old Nooelec TV tuner stick configured to handle the system I monitor in my office at work, running 24x7 even though I'm rarely there now.

Unitrunker 2.0 also works well but needs 2 SDRs.

For my use case SDRTrunk has been the easiest to get running - especially if you have access to the RR database and at least 2 SDRs or one SDR with enough bandwidth.

 

[boatbod]

Care to say what they are?

Care to do any research?

Windows: DSD+ Fastlane
Linux: OP25

 

[ChrisABQ]

Indianbrad, you really need the 2nd dongle. SDRTrunk does work great, I run my feed on Broadcastify with it. You don't need to program all the frequencies, just the main control channel and alternates (if you wish). Voice frequencies are automatically assigned (regardless of what they are) by the P25 control channel. IF you want a system that really works, get the second dongle, for $25 or $30, it's worth it.

 

[icemantim8]

I use one Noolec NESDR Smart with DSD+ Fastlane. I am monitoring the extremely difficult to receive State of Colorado DTRS Simulcast system in Colorado Springs, CO. Not as good as an SDS or Unication, but for the $, I am totally satisfied. There is a great FREE training session on SDR from W2LIE who runs Scanner School and East Coast Pagers. You may want to check it out for some really helpful SDR hints. I was up and running in a matter of hours after the training.


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[Indianabrad]

Windows: DSD+ Fastlane

I have all the vers of .Net from 2.0 to 5.0 but when I try to start that piece of ***** DSD+ it says that .Net is missing. I have verified that I have all the .Net vers with ".Net Verifier".

 

[dave3825]

The Monon site freqs span 8.4875 Mhz
The Rensselaer site freqs span 8.3125 Mhz

To use Sdrtrunk, you either need more dongles or you need to see if your in range of any of the sites whose freqs span less the 2.4375 Mhz. I looked before and there are a few there that would work if your in range. You only need to import the cc and the alternate cc's.

I could be wrong but I do not think .net has anything to do with DSDPlus. But I do know my DSDPlus Fastlane was working fine before I ever updated my .net to use the newer SDR#.

 

[boatbod]

I have all the vers of .Net from 2.0 to 5.0 but when I try to start that piece of ***** DSD+ it says that .Net is missing. I have verified that I have all the .Net vers with ".Net Verifier".

Since you are so angry at SDRTrunk and simultaneously think DSD+ is a "piece of ..." because you can't get it working, I'm coming to the conclusion you either have anger and patience issues, or are just a good old fashioned troll. Either way, please do me a favor and forgot I ever suggested trying op25 because it'll just infuriate you more since it requires thought and research to make it work. Have a nice day!

 

[PDXh0b0]

antenna issue? I was playing around with op25 for the first time today, got so flustered with myself I formatted and reinstalled linux, after re-installing the os and all the rtl dependencies, same results. I looked up and dang-it, I was using the wrong antenna. That antenna does work with sdrtrunk, so just need to get a handle on gain setting with op25. Hope you get it ironed out, they are all great programs listed above

 

[boatbod]

antenna issue? I was playing around with op25 for the first time today, got so flustered with myself I formatted and reinstalled linux, after re-installing the os and all the rtl dependencies, same results. I looked up and dang-it, I was using the wrong antenna. That antenna does work with sdrtrunk, so just need to get a handle on gain setting with op25. Hope you get it ironed out, they are all great programs listed above

For a typical RTL device a gain of 36-39 generally works pretty well. The easy way to determine the best gain is to run GQRX while watching the control channel freq in the spectrum display, then slowly increase the device gain until just below where the noise floor starts to rise appreciably.