No sound on a particular NXDN system.

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merlin

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Is there any criteria in decoding a NXDN48 CC where a call has no sound ? It did record a small wave file but all silence.
The log file shows a group/channel affiliation accepted and voice.
No problem on another NXDN system ??
73s
 

merlin

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I'm assuming you're using dsd+?
Is the frequency file have all the correct information?
DSD+fastlane. I can't confirm the voice channels but nothing in the frequency file.
This is a very quiet system, sometimes a few hours and not a peep.
A few lines from the log:
2021.07.29 7:59:55 Sync:+NXDN48 TB CCDATA SRV_INFO
2021.07.29 7:59:55 Sync:+IDAS VOICE e:7r4r7r7m
2021.07.29 7:59:55 Can't append to file '1R-DSDPlus.wav'; trying create instead
2021.07.29 7:59:55 Sync:+NXDN48 TB CCDATA SRV_INFO
 

sonm10

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You have to find the voice frequencies and add them to the frequency file or it will not work
There is very specific syntax for the frequency file, but there are examples to follow at the top.

You will also have to edit the network and sites files also for it to trunk track correctly. You can't just park it on the control channel like p25.
 

slicerwizard

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DSD+fastlane. I can't confirm the voice channels but nothing in the frequency file.
This is a very quiet system, sometimes a few hours and not a peep.
A few lines from the log:
2021.07.29 7:59:55 Sync:+NXDN48 TB CCDATA SRV_INFO
2021.07.29 7:59:55 Sync:+IDAS VOICE e:7r4r7r7m
2021.07.29 7:59:55 Can't append to file '1R-DSDPlus.wav'; trying create instead
2021.07.29 7:59:55 Sync:+NXDN48 TB CCDATA SRV_INFO
You haven't provided any log entries that actually show that there was any voice activity. A random bad decode means nothing.
 

merlin

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You have to find the voice frequencies and add them to the frequency file or it will not work
There is very specific syntax for the frequency file, but there are examples to follow at the top.

You will also have to edit the network and sites files also for it to trunk track correctly. You can't just park it on the control channel like p25.
Closest I can get are the channel numbers, maybe that math formula will work for this.
Network/sites, I will need to do some reading but looks like all the info I need is in the logs.
Something below may help.
 

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Kazzaw

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Easiest way to do this - I'm not sure if Americas system works the same way, but what I do here

Find the Site that the frequency is located on (FCC database I believe its called over there)
Look at the frequencies that are listed. Watch the control channel, wait for a group call to appear. Check the frequencies from the FCC database for traffic. Once you have found it, program it into your DSDPlus.frequencies (or whatever it is called) file using the examples. Open with notepad (or notepad++ is my personal preference). This tells DSDPlus where to tune to when a group call is started
 

merlin

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You haven't provided any log entries that actually show that there was any voice activity. A random bad decode means nothing.
I also watch activity on my spectrum analyzer, at least 2 spikes match the logging activity(other than CC)
Log shows 20 second append to wave file, real wave file is empty 2 seconds.
If these spikes are not voice they can only be data.
Easiest way to do this - I'm not sure if Americas system works the same way, but what I do here

Find the Site that the frequency is located on (FCC database I believe its called over there)
Look at the frequencies that are listed. Watch the control channel, wait for a group call to appear. Check the frequencies from the FCC database for traffic. Once you have found it, program it into your DSDPlus.frequencies (or whatever it is called) file using the examples. Open with notepad (or notepad++ is my personal preference). This tells DSDPlus where to tune to when a group call is started
Sadly, this frequency is not listed as yet in the FCC database and that does not have voice channels.
I have the CC channel frequency but only channel numbers for for voice. Given the formulae in the sticky is not even in the ball park, I have to get 2 frequencies the hard way (137 and 357). I watch the scrolling for hours before these channels get active, and then briefly. Narrow to 500Khz with the analyzer, then I can find it with the SDR.
(how I found the CC)
Hmm, whats with RR duplicating an old post.
 

merlin

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OK, took time but I worked up a formula to calculate frequencies on this particular system.
I got the frequency list fixed, that part is done, but I still get no decode audio, even in the wave file.
There is a TIII system adjacent, that works, the state P25p1 system works.
Something I am overlooking for this system.
My formula that works " ch# -1 X step size + the base frequency " Step is 12.5 Khz and the base is 450 Mhz.
This might work on another system. Nutshell, 450 - 174 Mhz into 12.5 Khz channels, each with a number starting with 1.
that problem solved didn't fix the sound issue though.
 

garys

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Also for NXDN on DSDPlus Band Width needs to be set to 4.
 

merlin

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For NXDN someone worked out the Channel - frequency table and posted it here,


It doesn't help with the newer narrower channel width frequencies which use custom channels.
Yea, that should work on systems with 12.5 Khz spacing and 450 Mhz base, and without a custom channel map.
For me, that narrows it down to one system of 4.
My formula comes up with the same results.
 
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merlin

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I am sure the no sound thing is just some setting I need to change but documentation doesn't detail such settings.
Can't change source input, it goes dead. Output is the same that works on other systems.
 
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