Uniden Trunking Issue

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jaskel

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This may be a NOOB question but here goes.

I have 2 scanners,

996T is on discone on roof, 396T is on RH701 whip, 396T receives 5 bars on motorola GRN with cont channel 416.4875 and the 996T is sitting on 2 bars on a different control channel and barely picks anything up on GRN...now why would the 396T on a different CC and more signal pick up tonnes more than the 996T??

Why is the 996T on the doscone grabbing a different control channel with less signal than the hand held on a whip??

I dont get it??

Now I have both on same CC and 5 bars signal each..i simply removed antenna untill it said FINDING C CHANNEL plugged it back in untill it found the same CC as the 396T and it picks up heaps more...i simply dont get it.

My ears are open to suggestions.

Cheers

Jas
 

hiegtx

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Dallas, TX
This may be a NOOB question but here goes.

I have 2 scanners,

996T is on discone on roof, 396T is on RH701 whip, 396T receives 5 bars on motorola GRN with cont channel 416.4875 and the 996T is sitting on 2 bars on a different control channel and barely picks anything up on GRN...now why would the 396T on a different CC and more signal pick up tonnes more than the 996T??

Why is the 996T on the doscone grabbing a different control channel with less signal than the hand held on a whip??

I dont get it??

Now I have both on same CC and 5 bars signal each..i simply removed antenna untill it said FINDING C CHANNEL plugged it back in untill it found the same CC as the 396T and it picks up heaps more...i simply dont get it.

My ears are open to suggestions.

Cheers

Jas
Hi Jas
The Uniden's will find, and return, to the first active control channel in a system. They won't then release the first channel found, then look for another, possibly stronger (or better one), also programmed in the same system and also scan it. The next time the scanner gets back to that system, it will return to the same control channel found the last time, if it can still be received, however badly.

I'm guessing that this may be the system you're trying to monitor. On a Motorola system, only one control channel, per site, will be active at any one time. (There may be several control channels listed, primary and/or alternates, but still, only one in use at any one time.) It sounds like you may have combined the control channels for more than one site (probably a couple sites , or more, near you) into one system file.

For your 396T, basically at ground level using a whip antenna, it can only "hear" the strong signal of the closest site. For the 996T, using a rooftop antenna at a greater height, it's finding that weaker control channel first, probably because it's entered before the 'stronger' one. It will then keep returning to that weaker c-channel, each time it scans that system, until that weak sister is totally unreadable. By disconnecting the antenna, you forced it to look again for a control channel, and this time the weak one was not there and it found the same, strong, signal as the 396T.

Your best solution would be to simply use the multi-site feature of the 996T. Enter the sites individually, so that it checks all of the sites, each time. (The less desirable, short term fix, would be to simply move the control channel frequencies for the stronger and/or closer site "up" to the top of the list, so that they are scanned first.) If you have combined sites on the 396 (as I think may be the case), and go mobile, at some point, you'd run into a similar situation where the scanner will be trying to "hear" a weak control channel, when a much stronger one is available. The best solution for the 396T, if you go mobile with it, would be to split it into individual systems (the 396T does not have a multi-site function; the new 396XT does). You can, in many cases, combine sites where they are far enough apart so that both sites' control channels are not in range at the same time.
 

rasputen246

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Jan 22, 2005
Messages
141
That explains a lot on my 2nd day with a 996XT.:D
Fine....nothing for 12hrs then fine again.
I went to the system area mobile and NO voice, good bars and lots of ID's.
Now after back inside, no gps, nice yagi 30 crowmiles & kicking at 2 to 4 bars. Mucho traffic.

It still may be my jacking around with all the colors (new toy) , and trying to do gps stuff. This thing has the potential to be AWSOME. As a roadwarrior of many years with a paper map, and now the gps along with the concept of Personal "Garmin"gps interface.
(if it has the correct output) It is mind blowing to see it L/O & U/L the systems.

Thanks for your great explaination........no vitrol at all, and understandable even to an "underachiever".:roll:
 
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