No decoded audio

[Jay Lijoi]

I see my aliases in "events", however, there is no audio decoded (they are not encrypted). I do hear some other random groups. I've tried for weeks now so I must be missing something.

The setting as set by Radioreference (for Passaic County, Little Falls and Woodland Park NJ):

New Jersey Interoperability Communications System (NJICS)
Control frequencies: 770.53125, 771.45625, 856.45625, 856.95625.
Settings: Control, Single, FDMA Phase 1

Alias Identifiers example:
Talkgroup 4267 Ptotocol:APCO-25

I would appreciate any help,

Jay

[sdrtrunk]

Since you're getting some audio, it sounds like you have the JMBE library setup.

Check the tuner PPM adjustment on all of your tuners.  If your traffic channels are being sent to a tuner that's out of adjustment, it won't decode correctly.

[Jay Lijoi]

I tried adjusting ppm but I'm not really sure how to adjust it. I set it in sdrconnect and hope it holds when I switch to sdrtrunk. Is there a procedure for setting ppm? 

[sdrtrunk]

Here's the section from the user's manual:

https://github.com/DSheirer/sdrtrunk/wiki/Tuners#ppm-correction

[dave38...@gmail.com]

I see my aliases in "events", however, there is no audio decoded (they are not encrypted). I do hear some other random groups. I've tried for weeks now so I must be missing something.

Control frequencies: 770.53125, 771.45625, 856.45625, 856.95625.

Site freqs are 7 and 800 mhz. What dongle(s) are you using? 

[Jay Lijoi]

I was using RSP1a and today I just received and am running an RTL. The results are the same. The Alias shows in "Events", however there is no audio out.  

[dave38...@gmail.com]

Post screenshots of each tuner in the tuner tab.  Ensure one dongle is tuned to the 7xx freqs and the other to the 8xx freqs. Ensure PPM is set correctly on both dongles.

[Jay Lijoi]

[charley....@gmail.com]

1.  771.18125 does not seem to be a channel used by NJICS according to RRDB.

2.  If you want to monitor the Passaic County site, you will need at least two sdr dongles, probably three:  1 for 700; 2 for 800 MHz

3.  You will need to assign each SDR a minimum and maximun (frequency) value.

4.  Your current SDR need more precise tuning - what brand / model is it?

5.  We can suggest more configurations once you obtain the necessary number of SDRs

[Tyler Durden]

I'm only seeing one connected tuner in the pic. The RTL. as Charley said you will want at least 2-3 tuners plugged in at the same time. Also turn up the master gain to max 495.

[sdrtrunk]

There's a section in the user's manual that describes how to adjust the (Master) gain on your tuner to optimize the signal strength and the signal-to-noise ratio.  Turning the gain to the max (495) is no recommended ... it's likely too much and it may make the problem worse.

[dave38...@gmail.com]

1.  771.18125 does not seem to be a channel used by NJICS according to RRDB.

Its not, its the center freq the dongle is using.

[Ryan Sullivan]

New Jersey Interoperability Communications System (NJICS) is a tricky system, in my idiot opinion. I'm locked on 858.6625. It DOES work if you find a strong control channel. I might be wrong but I have never had any success with control channels in the 700 mhz range. The meat and potatoes are always delivered in the 850-859 range. Local/county/agency are mostly stable. Talkgroups that pertain to State of NJ Agencies seem to change or be intermixed. Example: State police comms for a traffic stop heard on Turnpike road crew pothole repair talk group. Also, some local PD's show up on the B-Comm C-Comm etc talk groups. Then they disappear.