Having issues with the new dongles now. Will work perfectly when they are first turned on but after around 2 hours of usage when the dongles get hot they start with the choppy audio/poor decodes again.
SDRTrunk Issue with SDRTrunk P25 audio
- Thread starter dom6vrr
- Start date
Show the screen with the ppm settings for each dongle.
We can’t see the actual measured error, the pic is chopped. I also would not use automatic gain. It’s going to kill weaker signals and make matters worse. Need to see this..
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The Airspys use way more USB bandwidth than the RTLs.
I was getting freezes trying to run two Airspy minis with two RTLs
I added a PCIe USB card to my PC to get more bandwidth. Moved one each onto the new controller. That worked great.
I'm getting two more Airpsys today. Will have to see if my system can run that. I don't have anymore PCIe slots...
I was getting freezes trying to run two Airspy minis with two RTLs
I added a PCIe USB card to my PC to get more bandwidth. Moved one each onto the new controller. That worked great.
I'm getting two more Airpsys today. Will have to see if my system can run that. I don't have anymore PCIe slots...
I am not using Airspys
This is a response from the author on setting gain.
Tuner gain settings
groups.google.com
You basically have 2 choices.
Hit drop box and select Manual, and play with each setting individually to achieve what the author describes. A high signal peak and a low noise floor.
Or hit the drop box and choose a preset value to where the signal peaks high noise floor stays low.
Relatively high noise floor for the voice / traffic channels shown.
A couple of things have changed since I last posted on this thread.
1. My system now requires 4 dongles to pick up every voice channel. No problem for me since I had 2 NESDR Mini dongles left unused and 2 of my new Nooelec v5s.
2. I moved my antenna outdoors, resulting in much better signal and reduced noise/interference.
3. I have played around with the gain settings in SDRTrunk and think I have a good spot down.
With the change of moving the antenna outdoors, the audio and decode quality have been MUCH better. When I first turn on my setup for the day (I do not leave it running when I am not using my computer), the audio is immaculate, zero blips. Fast forward 3-4 hours later, things start going downhill. Decodes start getting worse where audio will cut out or skew so you miss a couple words or just sounds like poor reception on a phone call. This is pretty similar to the previous issue, but much less often. Overall, still much better than it was before moving the antenna outside.
I also noticed that this poor decode issue only happens on some of the voice calls. I did some watching and realized that when the signal is being decoded on a specific dongle, one of the Nooelec v5s, that is when the audio has issues. It could be both of the v5s but the second one is least priority and isn't used super much by the program. I also notice a higher noise level on the v5s compared to my NESDR Minis.
I was wondering what is causing this to happen? How can I resolve it? I have already tried playing with the gain to lower the noise floor, even making it higher to see what happens, but it doesn't get better if not worse. The only thing I can think of is heat? The v5s feel much hotter on the exterior than the NESDR minis. The v5s are literally hot enough to burn my finger if I hold it there long enough.
I greatly appreciate all the help and suggestions.
1. My system now requires 4 dongles to pick up every voice channel. No problem for me since I had 2 NESDR Mini dongles left unused and 2 of my new Nooelec v5s.
2. I moved my antenna outdoors, resulting in much better signal and reduced noise/interference.
3. I have played around with the gain settings in SDRTrunk and think I have a good spot down.
With the change of moving the antenna outdoors, the audio and decode quality have been MUCH better. When I first turn on my setup for the day (I do not leave it running when I am not using my computer), the audio is immaculate, zero blips. Fast forward 3-4 hours later, things start going downhill. Decodes start getting worse where audio will cut out or skew so you miss a couple words or just sounds like poor reception on a phone call. This is pretty similar to the previous issue, but much less often. Overall, still much better than it was before moving the antenna outside.
I also noticed that this poor decode issue only happens on some of the voice calls. I did some watching and realized that when the signal is being decoded on a specific dongle, one of the Nooelec v5s, that is when the audio has issues. It could be both of the v5s but the second one is least priority and isn't used super much by the program. I also notice a higher noise level on the v5s compared to my NESDR Minis.
I was wondering what is causing this to happen? How can I resolve it? I have already tried playing with the gain to lower the noise floor, even making it higher to see what happens, but it doesn't get better if not worse. The only thing I can think of is heat? The v5s feel much hotter on the exterior than the NESDR minis. The v5s are literally hot enough to burn my finger if I hold it there long enough.
I greatly appreciate all the help and suggestions.
Four dongles can be too much for one and possibly two USB busses to handle adequately. Another potential issue is that the program or OS is not managing memory efficiently. I would check that plenty of memory has been allocated to Java as a first step, then determine what busses are in use for your dongles. It would be helpful to post your entire SDRT startup log - that will show how much memory is allocated to Java and what USB busses are assigned to each dongle.
All of them are on 1 USB bus according to SDRTrunk, I am using this Anker USB hub that has its own power supply.
I allocated 6gb of Java memory a while ago, if what I am looking at is what you are talking about (screenshot attached).
Too many dongles for a single USB bus to handle reliably over time. I use two airspy wideband sdrs, and while they will work off of one bus, performance is much better and more reliable when using separate USB busses. Your Java memory allocation should be adequate.
Alright, I will try plugging them into individual ports on the computer and report back.
I just plugged them all into their own ports on the computer, but they are all still showing USB bus 1. Is that normal or am I supposed to be doing something differently to get them on separate ones?
It depends on the computer mainboard. More sophisticated mainboards (motherboards) typically have at least two USB busses; cheaper computers may only have one. Some hardcore people buy an expansion PCIE card that has four USB controllers that would provide for four additional USB busses. You should post a screenshot of your Device Manager expanded to show your USB ports. I'll post an example in a minute - I'm on my Macbook atm.
What brand and model motherboard are you using?
PRO Z690-A WIFI, I have an Aegis RS PC. It is pretty high end I thought
That is a high end PC; it should have at least 2 extensible host controllers that use different PCI lanes. My SDRT PC is an X570 and it has 4 extensible host controllers. I would experiment with different combinations of all the USB ports; I'm using a front port for one Airspy, and a
rear direct mb USB port for the second.
rear direct mb USB port for the second.
Here is what mine looks like. I pretty much tried every port and row. Also tried the top ports.
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