Unfamiliar In-band Signalling on Rocklin PD Dispatch

[CopperWhopper67]

Whenever I go through Rocklin I tune to their Dispatch frequency and along with MDC1200 I sometimes hear what sounds like a two-tone signal on keyup and sometimes on de-key. I have heard something similar to it on CHP's Valley Division-wide UHF frequencies but I am not sure what it is. I have audio of the signal that will be attached below. Does anybody know what kind of signalling it is? Apologies if this was the wrong section to post this.

Thank you

 

[gmclam]

I believe what you're hearing is a radio ID transmitted as DTMF. El Dorado Sheriff also has it as do many others.

 

[nd5y]

It's not DTMF. It sounds to me like tone remote.

 

[ke6gcv]

I found this thread that may explain the tones you're hearing: Radio/Repeater Tone Question?.

 

[dcr_inc]

Keying tone burst on the transmitter from the console.. The filter was not fast enough to clip it all before the TX came up