Pl?

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pogbobo

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its to decrease the chance of interference between two different agencies that may be near each other but use the same frequency ... and for a few other reasons too

to help you input it into your scanner we'll need to know what model you have, and it would be nice to know what systems you are trying to listen to as well ...
 

GrayJeep

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Pl

chedderhead said:
thats quite helpful but I still dont understand how I would do anything with that on my scanner?

I've found a few frequencies that I want to listen to also have a "stray" emission from some source that just opens the squelch and has nothing on it. These can be strays from my computer or my car's computer or the scanner itself or who-knows-what.

If the desired agency uses PL on that frequency then if I program the scanner to use the PL the radio will not respond to the stray but will open on the desired transmission.
 

JoeyC

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The Wiki article, while factual is vague in the eyes of a newbie.

Some things to remember about PL and DCS.

You NEVER need to program them to hear the transmissions.
You will want to program them in (if your scanner has the ability) if you are receiving interference from other stations or sources.
Think of PL and DCS as filters. 2 or more transmitters within your listening range may be transmitting on the same frequency. Without the PL or DCS enabled on your receiver, you would hear everything. By programming the proper PL or DCS the radio will only allow transmissions with the programmed PL or DCS to open squelch on the radio thus filtering those stations with different PL or DCS.
 
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pogbobo

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JoeyC said:
The Wiki article, while factual is vague in the eyes of a newbie.

Some things to remember about PL and DCS.

You NEVER need to program them to hear the transmissions.
You will want to program them in (if your scanner has the ability) if you are receiving interference from other stations or sources.
Think of PL and DCS as filters. 2 or more transmitters within your listening range may be transmitting on the same frequency. Without the PL or DCS enabled on your receiver, you would hear everything. By programming the proper PL or DCS the radio will only allow transmissions with the programmed PL or DCS to open squelch on the radio thus filtering those stations with different PL or DCS.

don't be afraid to update the wiki :):cool:
 

delta_p

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JoeyC said:
Think of PL and DCS as filters. 2 or more transmitters within your listening range may be transmitting on the same frequency. Without the PL or DCS enabled on your receiver, you would hear everything. By programming the proper PL or DCS the radio will only allow transmissions with the programmed PL or DCS to open squelch on the radio thus filtering those stations with different PL or DCS.

I got a pretty good lesson in PL other night while scanning. I am not a HAM radio operator but was listening to some fellas talking. One of the two guys talking was hitting two repeaters, one he intended too and another accidently which was several miles north of him but on the same frequency, and he was interefering with other's conversations (I only got the one side). Basically the problem was the distant HAM's had moved their repeater in the last few months closer to this operator and didn't have it set up on a PL tone. The operator tried everything, dialing down his power etc. It was really frustrating for this guy because he was caught between a rock and a hard place, and eventually he moved to a different less desirable repeater for these folks. Nice guy I thought.


PP
 

n2mdk

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Depends upon where you are but the best bet will be you will need to program everything into it.
 

af5rn

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chedderhead said:
Well, my scanner will be the 996T again. Thanks for the info, will I need to program anything into it?
LOL! That depends.

Do you want to listen to anything besides the main dispatch channel of the nearest big city police and fire departments? If so, you've got some programming to do. Good luck!
 

kb2vxa

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Rather than a long quote I refer you to Delta_P's last.

When I lived farther north I experienced the same problem keying a repeater in downstate NY while trying to use one here in central NJ. Low power and a beam were no help at all until finally the club put PL on the repeater. I no longer lit up that repeater unless I wanted to with the proper PL but I may have locked out the occasional user so I kept it short and sweet. Right, if a wanted signal can't override the unwanted "offender" the receiver won't hear it PL or no PL.

In another instance some more distant hams in a weekly net keyed up another repeater local to me being they're in a favorable mountain location. It was a rough row to hoe convincing old farts with ancient radios to add PL adapters (darn cheapskates) but the repeater finally got PL and everybody was happy including the stubborn old goats. (;->)

Now here's a twist many of you never heard of, anti PL. Two repeaters with PL, one having wide coverage and several remote "satellite" receivers interfered with each other. The one receiver getting clobbered got anti PL and the problem was solved. I just had to remember when in that area to turn the PL off.

To borrow a line from Paul Simon, a man hears what he wants to hear and disregards the rest... mmmm. So think of a receiver as The Boxer, that's the way it is when PL is on.

To underscore a previous comment;
"It was really frustrating for this guy because he was caught between a rock and a hard place, and eventually he moved to a different less desirable repeater for these folks. Nice guy I thought."

That's called good operating practice. As above even if the other repeater had PL he still would have interfered by blocking other signals on the input even if he didn't "light it up". That's why as always when I talked to someone on what now is a repeater local to me I kept it short. That was my only choice except not talking at all since there was no alternate repeater we had in common.
 
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jbreesefl

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PL's and Frequencies

i have an FM Frequency 115.1900. This is for the Bolton Fire service.
However, the Statepolice uses that frequency as well. the state police frequency is 115.11900 PL 118.8. My question:

To listen to both channels when programming my scanner, do i have to put the frequency in twice like this:

Freq Alpha Tag CTCSS
115.1900 Bolton Fire None
115.1900 StatePolice 118.8

Or, do i have to put the Freq in just once to listen to both channels:

Freq Alpha Tag CTCSS
115.11900 State Pol & Bolton Fire 118.8

Or
 

fineshot1

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jbreesefl said:
i have an FM Frequency 115.1900. This is for the Bolton Fire service.
However, the Statepolice uses that frequency as well. the state police frequency is 115.11900 PL 118.8. My question:

To listen to both channels when programming my scanner, do i have to put the frequency in twice like this:

Freq Alpha Tag CTCSS
115.1900 Bolton Fire None
115.1900 StatePolice 118.8

Or, do i have to put the Freq in just once to listen to both channels:

Freq Alpha Tag CTCSS
115.11900 State Pol & Bolton Fire 118.8

Or


You must be mistaken. Those frequencies are in the middle of the aircraft am band.
if you are receiving the state pd on them then you are receiving an image freq and
not the actual freq.
 

jbreesefl

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thanks for the response i made a typo.

take a freq that we can agree on 453.3000

say the state police uses it as 453.3000 PL 167.9. In addition say the Bolton Fire Department uses 453.3000 with NO PL.

My question is how do i program my scanner to listen to both of these organizations?

Is it A:
453.30000 167.9 Fire and police

or B with 2 seperate entries:
453.3000 167.9 Sate Police
430.0000 None Bolton Fire
 

jbreesefl

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another typo:

another typo!!! i really mean:

or B with 2 seperate entries:
453.3000 167.9 Sate Police
453.0000 None Bolton Fire
 

n2mdk

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To listen to both just put in the frequency without a PL you only need to program it once, it will pick up all transmissions made on the particular frequency.
 

jbreesefl

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thank you. now i see that the PL in this case is to be used to lock into a paticular group. so i f i want to only listen to the police then i use the PL and that will lock out other traffice on the freq.
 
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