155.475, 210.7

Hearing what sounds like a 1000 Hz. tone on 155.475, PL 210.7. It goes on for a few seconds and stops.

I suspect it is a tech tuning a radio.

I assume this is some sort of InterOp channel here (It is used as a police InterOp channel in the Midwest where I am from originally...) but this is the first traffic I have heard on it here in the year I have lived here.

this.

National Police VHF Channel

155.475

Use is limited to criteria set forth under Part 90.20 frequency limitation (41)”This frequency is available for use in police emergency communications networks operated under statewide law enforcement emergency communications plans”. Any request for this frequency must be accompanied by an affidavit indicating the use of this frequency is consistent with a state plan officially recognized by the state in which it will be used.

from
https://www.apcointl.org/spectrum-m...teroperability/interoperability-channels.html

N9JIG said:

Hearing what sounds like a 1000 Hz. tone on 155.475, PL 210.7. It goes on for a few seconds and stops.

I suspect it is a tech tuning a radio.

I assume this is some sort of InterOp channel here (It is used as a police InterOp channel in the Midwest where I am from originally...) but this is the first traffic I have heard on it here in the year I have lived here.

Click to expand...

I have lots of info, unfortunately most of it's old with little documentation. I have down that 155.475 is/was used by the Arizona AIRS (AZ Inter-agency Radio System) Arizona Interagency Radio System (AIRS) - The RadioReference Wiki . I also have down that it is Air Evac's channel 12 - Inter-Agency freq.

I have it programmed in my DEMA https://dema.az.gov/ bank where it's had 4 hits and in my medical bank where it's had 38 hits.

You might see if there is any info in the documents at https://casmnextgen.com/pslib/index.php/webview
Click the Area tab then Arizona.

I hear 155.475 with PL 156.7 frequently. This is the AIRS freq that is linked to 460.375 and 866.0125. What is unique is 155.475 with a PL of 210.7. That is not AIRS as AIRS does not use that tone.

The PL is what caught me by surprise as well. It was pretty strong out here so it might have been up on the White Tanks.