Pro-668 Donald Duck audio

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melonman07

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Hello all , I'm monitoring a large p25 system and many transmissions are sounding like Donald Duck at times just wondering if anyone else has this issue. Thank you .
Kevin
 

gewecke

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Hello all , I'm monitoring a large p25 system and many transmissions are sounding like Donald Duck at times just wondering if anyone else has this issue. Thank you .
Kevin
Welcome to the world of encryption, and no your 668 nor any other scanner will decode it...sorry. 73, n9zas
 

JD21960

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Pro668 Donald Duck audio

I have the WS1080 that's pretty close to the Pro668 set up. Yes. That's encryption. You didn't say if you downloaded ENC talkgroups on purpose, used a Wildcard for that trunked SYSTEM or what? But there is a setting on the scanner menu where you can chose SILENT, TONE or NOISE for that ENC noise when you do encounter it. *EncMODE should be in your settings ON the scanner somewhere. I have "TONE" on mine which sounds like a telephone busy signal.
 

melonman07

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It's not encryption, it has something to do with the decoding as I can hear the voices except at times it sounds like SSB on AM ,. I'm thinking there's a setting either in the software or within the radio .
Kevin
 

wbswetnam

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My guess is that it is voice-inversion, which is a weak analog form of encryption. It is easy to break and monitor but I'd get in trouble with RR if I explained it here.
 

cherubim

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My guess is that it is voice-inversion, which is a weak analog form of encryption. It is easy to break and monitor but I'd get in trouble with RR if I explained it here.

Voice inversion on P25 ? I don't think so.

The OP's problem sounds like multipath distortion. I often hear recovered audio on P25 sounding very robotic or duck like.

Encryption on P25 sounds more like bubbly water.
 

JD21960

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Pro668 dduck noise

Ahh... now that we have more information... Yes. Welcome to Simulcast Distortion. It's why I have to use a 700/800hz Yagi antenna at home.
 

JD21960

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Pro668 DDuck noise

Well that would be even MORE irritating knowing that. Might as well monitor Farcebook,twits or the local news instead of the scanner if that's the case
 

kd7mxi

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does it have clicks on the transmisions? ,,, taxi drivers in bullhead city use a ducklike sounding system were you can sort of make out words and phrases over time but just barely ,,, there on a analog system with reguler ctcss/dcs tone

in bandon Oregon and in Utah ive heard it used on maritime freqs that are linked to uhf freqs ,,, on the uhf side there often in the open
 
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gewecke

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Voice inversion on P25 ? I don't think so.

The OP's problem sounds like multipath distortion. I often hear recovered audio on P25 sounding very robotic or duck like.

Encryption on P25 sounds more like bubbly water.
I would agree with this analysis as well. :wink: 73, n9zas
 

N8IAA

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It's not encryption, it has something to do with the decoding as I can hear the voices except at times it sounds like SSB on AM ,. I'm thinking there's a setting either in the software or within the radio .
Kevin

Kevin, the only P-25 system up there is NYSEG. Is this the system you're trying to monitor? If so, since there is no listed towers in your county, do a CC analyze on the scanner. Pick the strongest signal on the CC, and put the multisite mode in OFF. This way the scanner will only pick up the tower you want.
With a system that large, you still might not escape the simulcast problem.
HTH,
Larry
 

melonman07

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Greetings again ,
I'm not sure yet what it may be , simulcast distortion, or maybe that the digital signal is slower to recover and transmissions are piling. Larry, currently I'm located in Onondaga County where there's multiple P25 systems , public safety , fire depts. , rescue co.'s etc. sorry I didn't put that info in my previous posts. Thanks for all the replies .
Kevin
 

N8IAA

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Greetings again ,
I'm not sure yet what it may be , simulcast distortion, or maybe that the digital signal is slower to recover and transmissions are piling. Larry, currently I'm located in Onondaga County where there's multiple P25 systems , public safety , fire depts. , rescue co.'s etc. sorry I didn't put that info in my previous posts. Thanks for all the replies .
Kevin

Go into your software, clear out any of the sites/frequencies that are not for your county. This should help somewhat with the scanner. After I replied, I saw that you had a 668, not a 652. My mistake. There is no where in the software to apply what I suggested. You might try a smaller antenna to receive the system, or use ATTenuation.
I have the PSR-800 and the WS-1088, and have no way to adjust LSM.
HTH,
Larry
 

KG4UDK

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Some of the Charlotte, NC Mecklenburg county CMPD frequencies have same issue with garbled transmission.
 
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