Open channels?

[ampulman]

Frequently, while searching for channels, the scanner (396) will lock on what appears to be an open carrier.

I am familiar with birdies and know that interference can cause a scanner to lock up. Strangely, some of these lock-ups show 1 - 5 bars on the display. Some of these frequencies appear in the FCC database, but many do not.

Can I assume that any channel showing 1 or more bars is an open carrier?

AM

 

[N_Jay]

Frequently, while searching for channels, the scanner (396) will lock on what appears to be an open carrier.

I am familiar with birdies and know that interference can cause a scanner to lock up. Strangely, some of these lock-ups show 1 - 5 bars on the display. Some of these frequencies appear in the FCC database, but many do not.

Can I assume that any channel showing 1 or more bars is an open carrier?

AM

No,

I would assume (if I had to make an assumption) that most if not all are internal or external birdies.

 

[gmclam]

Is there a CT (PL tone) associated with these carriers? If there is a tone, then a open carrier seems correct. With no tone it could be just about anything causing it.

 

[ampulman]

Is there a CT (PL tone) associated with these carriers? If there is a tone, then a open carrier seems correct. With no tone it could be just about anything causing it.

Thanks, I will turn tones on.

AM

 

[kb2vxa]

Hi Amp and all,

Turn WHAT tones on? Are you trying to monitor something specific on these channels? If you are using the specific tone for the transmitter in question will stop the lock-up but the wanted signal must be considerably stronger than the birdie to overcome it and capture the receiver. If you're not listening for something specific lock those channels out but in any case neither will work in search mode, you'll just have to keep punching the "scan" or "resume" button or maybe turn off the computer or other source of interference. If it's an internal design flaw you'll just have to live with it or get a better radio.

"s there a CT (PL tone) associated with these carriers? If there is a tone, then a open carrier seems correct."

No Clam, ain't no such animal, an open mic is soon found and corrected. He's got a birdie problem common to poorly designed digitally controlled frequency synthesized receivers or he's picking up his computer or some similar device, a common incidental radiator.

 

[gmclam]

open carrier does not equal keyed mic

Birdies are publicized frequencies for each scanner and should not even be programmed. No need to lock out something you haven't even programmed. ampulman stated he is familiar with birdies and so that issue was not addressed.

"s there a CT (PL tone) associated with these carriers? If there is a tone, then a open carrier seems correct."

No Clam, ain't no such animal, an open mic is soon found and corrected. He's got a birdie problem common to poorly designed digitally controlled frequency synthesized receivers or he's picking up his computer or some similar device, a common incidental radiator.

I said OPEN CARRIER, NOT a "keyed mic". Big difference. The carrier indeed can come from 1000s of places including what you've mentioned. ampulman did not indicate whether these signals were constant or intermittent. Indeed that fact would change how to handle the issue. If they're constant they'd need to either be not programmed, locked out, or perhaps move the antenna/receiver away from the source of the carrier. If they're intermittent then the logical question one asks is "do they have a CT?".

 

[kb2vxa]

GM, you assume too much, clam up.

SK

 

[N_Jay]

GM, you assume too much, clam up.

SK

Pot, Pot, Pot, DE Kettle!:lol: :lol: :lol: