UT not decoding one of the local P25 JNCR sites

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freqhopping

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My primary question is why can't I decode site 303 of this part of the JNCR system?
http://www.radioreference.com/apps/db/?sid=5163

This is closest of all of them. No matter how strong or weak I make the signal I still get nothing.

Here's a 30 second sample.


I can receive many of the federal P25 sites in my area. I noticed all the control channels sound different. What's the reason for this?
 
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Liverdog

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Hmmm...

Are the little tones (bleeps) every few seconds a problem in the recording or is that actually part of the control channel? There sure is a lot of high frequency 'hiss' (noise) and there is no low frequency component. How did you record this?
 
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freqhopping

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What you hear is exactly the way it is. This site is active, though very little.
I know of one TG for sure and it's encrypted, 1621. IDTracker has logged 1622 a few times.
I have not logged these TGs on any other JNCR sites.

All the JNCR and DOD sites have a little 'hiccup' or skip to them. The USMC sites don't do it.
If you're interested, you can download this zip with recordings of 12 other P25 control channels that I can receive tonight. I'm actually receiving a few distant ones I don't normally get. http://www.fileupyours.com/files/168735/CCs.zip

These are recorded through a discriminator tap with ScanRec.
 

freqhopping

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Unitrunker said:
I'll check this when I get a chance. Have you looked at the waveform in Uniscope?

Here it is with the volume set to the level that provides the best quality on the other systems.
010-0303.JPG



This is another site at its best quality, about 30% and UT works just fine on it.
008.JPG



Let me know if you need to see something else.
 

SCPD

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Hi Hopping;

freqhopping said:
Here it is with the volume set to the level that provides the best quality on the other systems.
Amusing domain name. I don't know what's up with the first image. Obviously not good for decoding. The second image looks quite good.

I wonder if the "blip" heard in the recording has any bearing on this.
 

dtscho

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freqhopping said:
I can receive many of the federal P25 sites in my area. I noticed all the control channels sound different. What's the reason for this?

I know this isn't related to Unitrunker, but I believe the reason that the control channels sound different for the various 380 MHz systems is because of the different manufacturers. I've noticed that all the JNCR system control channels sound alike (manufacturer: M/A-Com). The USMC systems (as well as Andrews) sound alike because they are Motorola systems.

Dave
 
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