BCD 396XT Noise after transmission is complete

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bchibb

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After a transmission is complete the scanner holds the signal (verified by signal strength meter) with no modulation (just a carrier) for several seconds (about 30) with a loud static. This seems to be happening only the 460.00-461.00 mhz range. It must be a setting on the scanner, but what is it?
 

ScannerWayne

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BCHIBB,

Look at your squelch level and bump it up one, possibly two numbers. That may work, but it probably won't. But it is worth trying.

Sounds more like you are listening to a freq that's part of a trunking system. But without knowing where you are and what system you're listening too, it makes it kind of hard to give you good advice.

Let us know how/if the above works.

Wayne...
 

krokus

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With this happening in only one narrow freq range, I would tend to think you are picking up an image or interference. Adjusting the squelch might help.
 

bchibb

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I've tried the squelch and that is not it. Which delay setting do I need to adjust? I believe it is a trunking system.It is the KY State Police and it does not do it on any other system that I have listened to. Any other ideas.

Also does anyone know why Kentucky is not pre programmed?

Is there a better antenna for this scanner?
 

ScannerWayne

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Delay won't matter; as long as a carrier is present the scanner will stay on the channel.

Same thing for an image or interference. As long as there is a signal present, the radio will hold on the channel until the signal is removed. Then the delay time will kick in and once that expires, the scanner will continue to scan.

From what the OP is describing he's getting a signal that continues to be present for 30 seconds or so after the conversation is complete. Sounds like a repeater actually.

Wayne...
 

bchibb

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A strong signal is present for the 30 +- secs., then the signal drops and noise goes away.
 

captclint

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Delay won't matter; as long as a carrier is present the scanner will stay on the channel.
Doesn't the 996XT have a couple of negative delay settings for just this purpose? I don't have one, but my 346 does, so I think XT models do. Never used it, so can't say how effective it would be in this situation. The bad news is that if is applied at the system level, so you might want to create a separate system for this freq or others in that range.
 
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ScannerWayne

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What eveyone is forgetting is that it's not the modulation that's breaking the squelch. It's the CARRIER that is breaking the squelch. Untill the carrier drops out, the scanner is going to hold on the signal.

Wayne...
 

bchibb

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It's like the carrier has not dropped. I'm still researching, but I haven't found any setting on the scanner that solve the problem.
 

trkntrlrman

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Just wondering if the ID in the frequency is always the same when this happens? Maybe they have a mic that is sticking for a few seconds when they relese it..
 

kruser

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Do the radios in a trunked system send an end code when PTT is release? If so, maybe they added this repeater hang on purpose to foil the scanner listener if it cannot also detect the end codes.
 

Gezelle007

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Sounds like you're listening to an LTR trunked system. When you listen to this kind of system on an actual programmed radio, you only hear audio when someone has their mic keyed. However if you're listening on a scanner, you hear everything. The repeaters often stay "open" for a period of time. 30 seconds sounds a bit long... but keeping a repeater open for a long period will help conserve its life rather than opening and closing everytime someone talks.
 

ak4fn

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From KY State Police Scanner Frequencies and Radio Frequency Reference

"several of the more commonly used responses to dispatch calls are automated whereas the trooper simply presses a button on his radio console to communicate "10-7", "10-8", etc. - on these communications, the dispatcher simply replies "10-4" unit xxxx."

This is data being sent back and forth that is keeping your scanner hung on the freq.

I have noticed they have been using it quite a bit more lately, Post 2 more than Post 1 (these are the posts that I monitor)
 

bchibb

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Bcd 396xt

I've been told by Radio Shack my problem is due to the 396XT not having triple trunking capability. Does this sound right??????? If so I need to sent it back for an exchange!!
 

UPMan

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RS is incorrect.

You need to be sure that Digital End Code Detect is turned on for the system and that squelch is not set too low.
 

trkntrlrman

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Don't listen to anything that Radio Shack Tells you, they no nothing.... Something in your setting is not right, This is a great Scanner and should have no problem with trunked systems. Check your Programming, and read the Manual also the wiki section on trunked systems....Read it till you understand it, and then read it again. as you read it check your prrogramming, and see that it corresponds to the mannual settings.
I see that your not a paid member here, and I would HIGHLY advise getting a membership. it's invaluable.
Being able to download from the data base is worth every penny you pay.. Again Good luck ...
 

kruser

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I've been told by Radio Shack my problem is due to the 396XT not having triple trunking capability. Does this sound right??????? If so I need to sent it back for an exchange!!

It is apparent that the person at Radio Shack does not know Sh*t from Apple Butter.

Do as UPMan suggested and I think you will find that things work really well.

I did have a channel here once that resulted in noise when the repeater dropped. I found that it was caused by interference on the exact frequency so the squelch did not want to release at the end of transmission. When the repeater dropped, there was still an interfering signal that held the squelch open for about one second. I was able to work around that one by a higher squelch setting just as UPMan mentioned. This signal was much weaker than the intended signal but you could here a change in the white noise when you tuned that frequency with the squelch open indicating some type of interference.
This interference was tracked to a noisy desktop computers power supply.
 
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