SDRTrunk SDRTrunk questions

[Bdadswell]

Hello all;
Absolute SDR newbie here.

I’m trying to set up SDRTrunk to hear my county’s emergency services.

I’ve followed all of the directions and videos I can find, but I’m still not getting any audio.

I have a control frequency locked in, and I’ll see partial identifiers in the events window, but nothing accurate and no audio.

My signal appears to be good, bouncing from 19-23.

For reference, it is Genesee County in NY. Here is a screen shot of my set up.

Anything seem glaringly out of place?

 

[Enforcer52]

Have you installed JMBE Library and ran CPU Vector Calibration?

Have you set the PPM and Master Gain for the sdr?

Have you set up an Alias list for Genesee Co?

 

[Bdadswell]

Have you installed JMBE Library and ran CPU Vector Calibration?

Have you set the PPM and Master Gain for the sdr?

Have you set up an Alias list for Genesee Co?

I’ve done the JMBE Library and ran the calibration. I have also set up the alias list and imported into the playlist.
As far as PPM and master gain, the master gain is 495 and the PPM is at -5.106 but the auto-adjust is checked.

 

[Enforcer52]

Is the sdr a RTL-SDR? Inside or Outside antenna?

I have never seen a sdr run -5.106 on ppm (My worst is only -3.9). Did you set it to that or did it show something else when you first hooked it up. If it is too far off frequency it will not do the auto adjust. When you do hear traffic what is the ppm showing? It should be with 200Hz. If it shows any other value that is higher then you need to adjust the ppm manually till you get it within 200Hz then the auto adjust will kick in. If it shows a postive Hz signal then adjust to the negative, if it shows a negative Hz signal then adjust to the Positive.

I would lower the ppm to around -2.0 and then watch it and adjust in up or down according to what is is showing as difference in the Tuners window.

If you continue to have issues shoot me a PM with your phone number, easier to troubleshoot over the phone.

 

[C_615]

What type of system are you trying to monitor and what version of SDR-Trunk are you using?

 

[dave3825]

Show some of the following screens. Please use Windows snipping tool for that if using Windows.

 

[Whiskey3JMC]

Welcome to the RR forums @Bdadswell
Screenshot's too dark & blurry at parts so I'm unable to make out certain text. You'd be strongly advised to use Windows' Snipping tool to post screenshots rather than taking blurry pictures of your screen

Show some of the following screens. Please use Windows snipping tool for that if using Windows.

Did we really give the OP the same suggestion at the same time? Simulcast posting

 

[DaveNF2G]

Did we really give the OP the same suggestion at the same time? Simulcast posting

And no distortion!

 

[Bdadswell]

Sorry for the delay guys - I was swamped yesterday at work. Here's some screen shots. I am able now to hear one trunked group but not any others. I have ensured that all aliases are enabled for audio, and still can't get the rest to work.

 

[Bdadswell]

What type of system are you trying to monitor and what version of SDR-Trunk are you using?

I am trying to monitor our local emergency services channel. It's a P25 Phase II. I am using version 23.0.1 for OS

 

[Enforcer52]

First thing I would do is take the Master gain control off of Automatic, it doesn't work well on automatic, and set it to 495 to begin with (you can adjust down later once you get the system receiving correctly).

Then watch the PPM when a signal is being received and see what the measured error rate is, if more than 500hz off then adjust the PPM. And monitor the PPM rate and continue to adjust it if over 200Hz.

I noticed the PPM was running around 1085Hz, which is way off, but it may change once you set the Master gain to 495.

 

[dave3825]

It's a P25 Phase II. I am using version 23.0.1 for OS

You mean JDK 23.0.1?

Your ppm is off.








Hit the up and down arrows to get the measured error as close to 0.0 as possible.

I am able now to hear one trunked group but not any others. I have ensured that all aliases are enabled for audio, and still can't get the rest to work.

You will only hear tg's that affiliate to the site your monitoring. Which tg's are the ones your not hearing?

 

[Bdadswell]

I adjusted my PPM to .32 and it got my measured error right around 100Hz, I am able to hear the main channel I wanted to hear, so I think I am making progress.

 

[Whiskey3JMC]

I am able now to hear one trunked group but not any others.

According to this calculator you'd need a 2nd RTL dongle to cover the last frequency on the on the Orleans County site. Per that calculator, only one dongle is needed to monitor Genesee County but if you add Orleans County into the mix or monitor Orleans County alone then a 2nd dongle would be needed

Both Genesee County & Orleans County


Orleans County alone

 

[Bdadswell]

According to this calculator you'd need a 2nd RTL dongle to cover the last frequency on the on the Orleans County site. Per that calculator, only one dongle is needed to monitor Genesee County but if you add Orleans County into the mix or monitor Orleans County alone then a 2nd dongle would be needed

Both Genesee County & Orleans County
View attachment 184785

Orleans County alone
View attachment 184788

I'm not super concerned about Orleans County right now. Once I can get Genesee County fire and EMS operations tuned in and running then I'll get a second dongle and add in Orleans - great info to know - I'm super new at this and appreciate all the help!

 

[Enforcer52]

I adjusted my PPM to .32 and it got my measured error right around 100Hz, I am able to hear the main channel I wanted to hear, so I think I am making progress.

Good, now it's a matter of monitoring for awhile and see what the PPM does. Auto adjust should maintain it close to what it needs now.

Waterfall is not showing a lot of background noise, so I would leave the gain at 495 for now.

Are you on an inside or outside antenna?

 

[Bdadswell]

Good, now it's a matter of monitoring for awhile and see what the PPM does. Auto adjust should maintain it close to what it needs now.

Waterfall is not showing a lot of background noise, so I would leave the gain at 495 for now.

Are you on an inside or outside antenna?

for right now, inside. The next project is using a second dongle to set up SDR++ to monitor a 400 MHz channel.

 

[Enforcer52]

for right now, inside.

As always an outside antenna would work much better.

The next project is using a second dongle to set up SDR++ to monitor a 400 MHz channel.

Why SDR++ for the 400MHZ channel and not SDRTrunk, any particular reason for SDR++

 

[dave3825]

The next project is using a second dongle to set up SDR++ to monitor a 400 MHz channel.

What is the channel? SDRT can monitor single channels also.

 

[Bdadswell]

@Enforcer52 and @dave3825 - I wasn't sure that SDRTrunk could monitor it. When I went to the RadioReference tab, I can't find the system I'm looking for. Here is what I am trying to monitor, with the primary channel being 424.400 (It doesn't show up on RR, but that is the main dispatch frequency for Amherst Fire Ch. 1, and the 424.125 is the repeater.