Mystery control channel Control channel 774.634375?

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Stavro35

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Control channel 774.634375 sys i.d 1f1 radio displaying that it is a p25 frequency . I thought it might be the new King county transit system . I don't show that frequency for that system and the sys i.d doesn't match.

Is this a mirror image of an existing system ?

Is this possibly the new state DOT system rumored to be in place?

Any information or speculation even would be appreciated.

Steve
 

W2GLD

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If it's a GRE or a Radio Shack scanner, then it's an image from a 800 MHz. frequency; it's a common problem with those scanners as they have very poorly filtered front ends...
 

Stavro35

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Thanks it is in fact the Radioshack Pro106. .I figured it had to be an image, as I couldn't find anything for it. And the last digits were soooooooooooooooo loooooooooooong.
 

ChrisP

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Control channel 774.634375 sys i.d 1f1 radio displaying that it is a p25 frequency . I thought it might be the new King county transit system . I don't show that frequency for that system and the sys i.d doesn't match.
That frequency does show up as an alternate control channel for the King County Metro Transit System, site 001. I don't know why the system ID is not the same, but it is close:

King County Metro Transit Trunking System, Seattle, Washington - Scanner Frequencies

- Chris
 

W2GLD

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That frequency does show up as an alternate control channel for the King County Metro Transit System, site 001. I don't know why the system ID is not the same, but it is close:

King County Metro Transit Trunking System, Seattle, Washington - Scanner Frequencies

- Chris
Easy way to rule this out is to see what control channel is active on that system; only one can be active at a time... I'd put money on it being an image in the radio and NOT an actual control channel! There's a reason I'll never own another GRE/Radio Shack/Whistler scanner; their receiver front ends suck...
 

mtindor

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Control channel 774.634375 sys i.d 1f1 radio displaying that it is a p25 frequency . I thought it might be the new King county transit system . I don't show that frequency for that system and the sys i.d doesn't match.

Is this a mirror image of an existing system ?

Is this possibly the new state DOT system rumored to be in place?

Any information or speculation even would be appreciated.

Steve
If you're getting a decode on it and it's reporting a SysID that isn't already in the DB, then you don't want to completely overlook it. If it's an image, then the frequency isn't correct -- but you have found a new system and it may be of benefit/interest to you to attempt to figure out what system it is.

Is the signal strength strong? If so, then turn on your attenuator and see if you can still pick it up. If you can still pick it up with your attenuator on, I would certainly investigate further the possibility that it is a 700 mhz signal and not some image from somewhere else. No matter how you slice it, that frequency is not absolutely correct, but if it is truly a 700 mhz transmission then the true frequency would be just slightly above or below that frequency.

Now, if the SysID was one that was already known in the DB, then you could easily determine whether it was an image or not. But since the SysID is different, you can't tell for sure.

If you actually get a good decode on it, hook up your computer to it and run Pro96Com. if it's truly a P25 control channel and if you can get any kind of decode on it, you'll be able to know the true frequencies because the control channel will be reporting that information and Pro96Com would pick it up. If it's an image from another band, as long as you can get a good decode on it Pro96Com will reveal the true frequency.

Mike
 

scannerizer

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Thanks it is in fact the Radioshack Pro106. .I figured it had to be an image, as I couldn't find anything for it. And the last digits were soooooooooooooooo loooooooooooong.
I thought it had something to do with the Puget Sound Emergency Radio that was discussed in another topic in this specific forum. Still, good to know.
 
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