Why is the transmission garbled ?

wisconsinjimmy

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Cushing, Polk, WI
I have the Digital Trunking scanner and I monitor Polk County WI, one of the cars, when he transmits, is all garbled yet dispatch has no problem understanding while other cars cannot understand what is being said, dispatch is not garbled and I can understand with no problem.
 

Whiskey3JMC

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Is this the frequency in question? If you can hear dispatch to cars but not cars to dispatch perhaps you or someone local who can confirm it should submit a change to the Mode field below to make it "P25e" with lowercase "e" indicating partial encryption. If not the frequency in question could you let us know what is?

Polk County
FrequencyInputLicenseTypeToneAlpha TagDescriptionModeTag
155.55000158.85000WQFA852RM490 NACPOSOSheriff DispatchP25Law Dispatch
 

gmclam

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What sounds garbled can come from 3 places on a GRE P25 scanner:
1) The signal is encrypted. Over time you can tell the difference between this and the two below:
2) Weak signal. In the analog days we had static, now it comes in the form of poor digital decoding. Are you using a portable antenna or something serious? How far away is the signal? All part of determining if this is your case.
3) Simulcast. This is where the signal is being transmitted simultaneously from more than one physical location on the same frequency. There's only two models that can handle this and neither made by GRE or Whistler.

Don't confuse signal strength with signal quality. In the analog TV days, you could get a very strong signal with lots of ghosts. You're more able to see a weak signal with no ghosts. Digital has similar pros and cons depending on signal being transmitted, receiver, receiver decoder settings.
 

Mikejo

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One way to get around simulcast with a GRE or Whistler scanner, is to use a vertically polarized Yagi. Find out which of the simulcast antennas is closest to you, and point it at that Antenna. 😎
 

kruser

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The garbled transmission is likely an encrypted transmission. Only radios programmed to decode the encryption will be able to monitor the transmissions.
Should not actual subscriber radios mute the encryption noise if they don't have the proper key?
The OP says other mobiles also cannot understand the user that is likely encrypted. That tells me the others on the system without the encryption key are using radios that are still passing the noise of an encrypted signal. I'd think any manufacturers radio would mute the horrible noise of E and not let it pass to the speaker. That would be a horrible distraction to the others.
 

mmckenna

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Should not actual subscriber radios mute the encryption noise if they don't have the proper key?
The OP says other mobiles also cannot understand the user that is likely encrypted. That tells me the others on the system without the encryption key are using radios that are still passing the noise of an encrypted signal. I'd think any manufacturers radio would mute the horrible noise of E and not let it pass to the speaker. That would be a horrible distraction to the others.
Depends on how the radio is set up. Kenwood radios can be programmed to pass encrypted/garbled audio if the radio doesn't have the key, or it can be set to mute.
 

Danny37

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Usually when this happens to me, its either im getting a poor signal or something nearby is interfering. Also, if you're on the move it could be your surrounding terrain
 

Mikejo

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Interestingly enough, I have an old GRE-PSR 800 which was upgraded to a WS 1080 and a friend gave me a code plug for the Boston area, interestingly enough, when it encounters an encrypted transmission, it plays an old telephone “busy signal“. I don’t know how this was implemented, as the code plug was given to me.
 

tvengr

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Interestingly enough, I have an old GRE-PSR 800 which was upgraded to a WS 1080 and a friend gave me a code plug for the Boston area, interestingly enough, when it encounters an encrypted transmission, it plays an old telephone “busy signal“. I don’t know how this was implemented, as the code plug was given to me.
Using Whistler WS1080/WS1088 EZ Scan, go to the Advanced Features and Audio Options tabs. Under Encrypted Digital Audio Settings, you can set the Audio Mode to Digital Noise, Silence, or Audio Tone.
 
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