SDRTrunk SDRTrunk Losing Control Channel

[W5ATX]

I searched but only found a few threads saying the reception was an issue but that's not the case here. I live across the street from a P25 P1 and P2 site, while running my airspy mini for about an hour suddenly SDRTrunk will lose the control and show Idle (sync loss). When it does this, the waterfall is still visible at the top and the control channel is still broadcasting, this was also confirmed by a different scanner monitoring said control channel. I also noticed there's some glitches going down the waterfall, again i listened to the CC with my scanner and there's no interference or strange noises coming thru the speaker. I can adjust the gain but it has no affect. To put the icing on the cake, I just purchased this airspy mini and the chipset is not the same one as advertised, maybe I have a defective unit? If you have any idea why SDRTrunk keeps dropping the control channel please chime in.

 

[nick0909]

I have been using trunk-recorder on linux but recently tried switching to SDRTrunk on Windows. I saw the same issue. I have tried with an airspy mini like you as well as a nooelec and both will track strong for ~30 minutes, then the audio starts to get glitches, and then it goes idle like you are seeing. These are the same SDRs that I have had running on trunk-recorder without issue for over a year, so I don't believe reception or the radio is the issue. The decoder just seems to be not as robust, I'm hoping to figure out ways to make it better and more reliable because I would like to retire my linux server that is doing this task now. I was using the latest 0.5 beta 5, I'm not sure if other versions do better or worse.

edit-my system is also P25 P1.

 

[W5ATX]

I'm thinking it's SDRTrunk software related too honestly. I restarted the program and it worked for about 3 minutes and then crapped out again. I'm glad there's someone else having the same issue as I am. It was working great for about an hour, and i've only played around with this program a couple of times. My plan was to put this on a dedicated computer and upload to Broadcastify Calls. Right before this started happening I noticed something else. I had entered the 3 alternate control channels in the program. After 5 minutes, it would "lose" the main control channel and go searching for a different CC. I was watching the waterfall shift every 400ms (default frequency rotation delay time). It would go right right past the CC every time while it was still actively transmitting, it took a few trips around before it finally locked on. It did this several times, and then it decided not to lock on to the CC at all , it would show Idle and also it would show a single line and say Active in blue but there was no audio. I wiped the folder and re-installed SDRTrunk fresh and it's still doing it. My PC is a fast Alienware i7, plenty of ram, etc. This was decoding 15 active voice channels simultaneously on the Gatrrs system here in Austin just a few days ago with no issues. I know these things get warm, but it's not that hot in my opinion. the Flir shows the casing was 109F. my old RTL-SDR v.3 ran way hotter. frequency error is about the same even tho the TCXO is supposed to be 2x more accurate. I have to adjust the ppm shift at -1300 a few minutes after initial power-up. I'm bummed and feel like I wasted $115.

 

[dave3825]

What version of sdrtrunk is being used? I had some issues along the way but am right now running beta 3 24/7 with a nooelec and an airspy mini.

 

[noamlivne]

I searched but only found a few threads saying the reception was an issue but that's not the case here. I live across the street from a P25 P1 and P2 site, while running my airspy mini for about an hour suddenly SDRTrunk will lose the control and show Idle (sync loss). When it does this, the waterfall is still visible at the top and the control channel is still broadcasting, this was also confirmed by a different scanner monitoring said control channel. I also noticed there's some glitches going down the waterfall, again i listened to the CC with my scanner and there's no interference or strange noises coming thru the speaker. I can adjust the gain but it has no affect. To put the icing on the cake, I just purchased this airspy mini and the chipset is not the same one as advertised, maybe I have a defective unit? If you have any idea why SDRTrunk keeps dropping the control channel please chime in.
View attachment 129728

I also have this. When Idle happens, go to the Tuners tab, and change the PPM value just a bit (up or down), and/or enable/disable the Autocorrect box. That should whack the program back to life (till the next time it happens - then repeat). I think it's a bug. Others have it as well.

 

[W5ATX]

What version of sdrtrunk is being used? I had some issues along the way but am right now running beta 3 24/7 with a nooelec and an airspy mini.

0.5.0-beta5

 

[wgbecks]

I have found that when running SDRTrunk, and especially with Airspy devices that it's necessary to either increase the Master Gain control
for the tuner (SDR). However, my preference, based upon experience, is to operate the Airspy using the "Custom" gain option wherby I have
set the LNA Gain to 14, the Mixer Gain to 10, and the IF Gain to a value of 8. Keep in mind that if you are operating very near the tower site then if will be necessary to reduce the LNA Gain downward to prevent overloading of the SDR, and in some cases you may also need to lower
the Mixer Gain as well.

 

[W5ATX]

I tinkered around with everything. usually i run the gain around 13-15, the tower across the road I'll lower it to 10, that seems to get around -40dBm +/- it had no affect on the lines on the waterfall or the program losing the control channel. thanks for the feedback. it may be a combo of the nature of this program and a glitchy airspy.

 

[wgbecks]

Check that you don't have any of the AGC boxes checked in your tuner configuration.

 

[W5ATX]

I've tried it all, this thing is acting wonky, it's also the wrong chipset as advertised. I'm already in a dispute with PayPal with the seller, I'm familiar with who the seller is.

 

[BMDaug]

With my RTLSDR, I was having intermittent control channel issues and I ended up lowering the sample rate and it’ll run for days that way with zero perceivable negative effects… I’m also running it on an Apple M1 Mac Mini so your mileage may vary given the differences in hardware.

-B

 

[ronenp]

I have reported it a while ago also
Try to reduce the receiver sample rate to 5MHz and not as i see here 10 Mhz
it is definitely software issue

 

[dave3825]

Try to reduce the receiver sample rate to 5MHz and not as i see here 10 Mhz

Op is using an Airspy mini. The only supported sample rates for the mini are 3 or 6MHz.


@W5ATX if the freqs in the site your monitoring equal less than 3MHz, you can go with a 3MHz sample rate. If the freqs exceed 3MHz but are less than 6MHz, you can use what your using now. My system is over 3MHz and I run it 24/7 @ 6MHz.

I just purchased this airspy mini and the chipset is not the same one as advertised, maybe I have a defective unit?

Can you elaborate on that more? Where did you buy the Airspy Mini and where is it displaying the wrong chipset?

I restarted the program and it worked for about 3 minutes and then crapped out again.

When you start Sdrtrunk, the dos/cmd window comes up. That will display all of the environment and hardware details. It will also display any errors sdrtrunk encounters. Can you do a screengrab of the last error listed and post it? It will look something like this. (my error shown is due to the 3rd dongle being used in Unitrunker 2.0)

 

[W5ATX]

I always watch the startup details, sometimes it will receive errors and still work, other times there's no errors and it still has issues which I don't understand. I have tried both 3 and 6 MHz bandwidth, it will receive some of the higher oddball channels in the 6 MHz Spectrum which is technically 4.8 according to what I read somewhere. This thing just does whatever it wants to, there's one control Channel on an LSM system here in Austin, the tuner frequency seems to jump around on its own which is no big deal I assume it's kind of centering the window around the lowest and highest frequency, sometimes it will jump out of the spectrum and wind up on a weird frequency that is not the control channel that I entered and just sit there. there's been a lot of teardowns getting stuck as well.

On the flip side I'm fighting with airspy because they sent me an older model than what I purchased, there's a minor discrepancy with the chip number but regardless that's another story. The whole thing has been a bad experience and I've decided to scrap it, not worth the fuss and bother at this point. Thanks to all that have posted.

 

[Morondevous]

Just found this thread, will be following. Before I found this I posted at the SDR trunk Google Group Support here.

Sounds like I have identical problem. Before I blame the software, I really want to make sure my USB ports are good etc. If you have any tips for me to try in addition to what ive posted on the google group, I'd be interested.

Thanks

 

[a417]

To put the icing on the cake, I just purchased this airspy mini and the chipset is not the same one as advertised, maybe I have a defective unit?

defective or counterfeit/knockoff?

 

[Morondevous]

Just found this thread, will be following. Before I found this I posted at the SDR trunk Google Group Support here.

Sounds like I have identical problem. Before I blame the software, I really want to make sure my USB ports are good etc. If you have any tips for me to try in addition to what ive posted on the google group, I'd be interested.

Thanks

I've found this post. I have implemented this, and it has effectively stopped my dongles from jumping around. So far, all is well. I'll try and post results here after some time.

 

[Morondevous]

I've found this post. I have implemented this, and it has effectively stopped my dongles from jumping around. So far, all is well. I'll try and post results here after some time.

This fixed my problem. Audio and great!

 

[nick0909]

I've found this post. I have implemented this, and it has effectively stopped my dongles from jumping around. So far, all is well. I'll try and post results here after some time.

Interesting... I tried this method and found my AirSpy Mini, when set to 3mhz bandwidth, would only actually let me tune about 2mhz at once in SDRTrunk, anything beyond that it would say no tuner available. The system I want to cover is 2.2mhz wide. I use the same dongle in trunk-recorder on 3mhz and it works no problem. I have changed it to 6mhz and will see if it manages to keep a lock on the system now, but kinda disappointed I have to burn extra CPU on 6mhz when really 3mhz should work...

 

[Lexxx]

Just thought I'd chime in here as I was having problems with my sdrtrunk .0.5.0-alpha6 with the dongle plugged into a powered USB hub. I'd lose the control channel and the program would often close down.

After plugging directly into a usb outlet on the computer (I'm using an HP Mini) my problems seemed to disappear. Sdrtrunk very stable now since that change. I'm monitoring the local Fire Department on a P25 phase2 sytem.