Frequency Overlap?

[emsflyer84]

Hey all,

Just curious about this situation... I'm in Carroll County and I have Saco Valley FD dispatch (Fryburg, Maine) programmed in my scanner. They share a frequency with Rockingham County, NH fire dispatch. I pick them both up equally well on my scanner. Just curious about how these two dispatch centers don't constantly talk over each other or interfere with each other. I'm sure there is some technical explanation, I'm just curious. Thanks!

 

[potala1369]

Using different PL codes????

 

[jaspence]

If you are not using PL tones for receive, you will hear any transmission on a frequency regardless of what the individual dispatchers use.

 

[emsflyer84]

If you are not using PL tones for receive, you will hear any transmission on a frequency regardless of what the individual dispatchers use.

I'm sure this is all it is. Thanks.

 

[ecps92]

AS others have indicate the use of PL/DPL also known by other names in the past CTCSS/Channel Guard, DCS etc
and now with P25 the use of a NAC eliminates the "Microphone on-hook" issues of not hearing the other users.

Also the distance separation between the two users in miles, where most likely they [other than a base station] would not hear each other.

Hey all,

Just curious about this situation... I'm in Carroll County and I have Saco Valley FD dispatch (Fryburg, Maine) programmed in my scanner. They share a frequency with Rockingham County, NH fire dispatch. I pick them both up equally well on my scanner. Just curious about how these two dispatch centers don't constantly talk over each other or interfere with each other. I'm sure there is some technical explanation, I'm just curious. Thanks!