Band Sensitivity for Close Call

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Gilligan

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On my BC246T, when I use Close Call w/ both VHF and UHF enabled, it hardly picks anything. But when I select only VHF or UHF, it works much better. For example, I was at an airport and an employee keyed up his handheld about ten yards away. I had VHF Hi and UHF enabled for CC. Nothing. Turned of VHF Hi and nailed the UHF freq right away. Why does the interference (and I think the "RF field") on VHF affect UHF readings? I'm not sure if I really understand how Uniden's Close Call works, especially with different bands selected. Thanks
 

mancow

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It may have less of a noise floor to compare against signal spikes when constrained to one single range as opposed to a broad range that includes numerous higher powered signals.
 

Gilligan

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mancow said:
It may have less of a noise floor to compare against signal spikes when constrained to one single range as opposed to a broad range that includes numerous higher powered signals.
Okay, that's the answer I was looking for. Now I'll just dwell on that for a while....
 

Ubbe

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It doesn't work that way. Set the scanner to CloseCall priority and open up the squelch so you will hear the noise.

Now go inte CC bands in the menu and set all bands to ON. Go to MAN and listen to how long time the noise gets interupted from the CloseCall check.

Now set all bands off except one and listen to the noise again. You will notice that it is a much shorter time.

The CloseCall will "search" each band individually in sequence and not all at the same time in parallell. It doesn't at all work as a Scout, with millisecond response, even if the end result are almost the same with RF carriers lasting longer than 1-2 seconds.

Ubbe.

mancow said:
It may have less of a noise floor to compare against signal spikes when constrained to one single range as opposed to a broad range that includes numerous higher powered signals.
 

Gilligan

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I tried your idea and there doesn't seem to be any difference in how long Close Call runs. We're talking like a fourth of a second either way w/ mine, unless I'm messing it up. I'm assuming by Close Call Priority you mean simply having close call on in the background while holding on a channel w/ open squelch.

On that note, then, does the squelch control have any effect on Close Call sensitivity?
 

Napalm

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In my 330T I can hear the difference between having one band on, and having all of them turned on. It's a good 500msec (not measured).
 

wolter

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mancow said:
It may have less of a noise floor to compare against signal spikes when constrained to one single range as opposed to a broad range that includes numerous higher powered signals.
Paul Opitz has said that transmissions in separate bands to not affect eachother. So, whatever is happening in one band will not prevent capture in another.

http://groups.yahoo.com/group/BCD396T/message/13232
 

morfis

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wolter said:
Paul Opitz has said that transmissions in separate bands to not affect eachother. So, whatever is happening in one band will not prevent capture in another.
No, but if it has to "scan" more than one band it is more likely to miss a transmission (which is what napalm and ubbe imply in their replies)
 

Gilligan

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Does squelch control affect Close Call sensitivity?

Nevermind -- I'll start a new post for this question.
 
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