Two Tone Signalling Prior to Sig Alert Broadcasts

[wildwing]

In Orange County (CA), Control One broadcasts Sig Alert Traffic Bulletins on OC Access (151.085). Just before the broadcast, a two-tone signal is heard. What is exactly is this two-tone signalling called, and how can I filter it out from my MT2000 (assuming that's even possible)? I do notice that on County 800 MHz subcriber units, this two-tone signal is not heard, but the broadcast is.

Thanks,

 

[Markb]

It's called 2+2. At least that's the only name I've ever heard it referred to as.
There's no way to filter it out.
The tone generator is only on the VHF side, so the patch only carries the voice. So I think that's why you won't hear the tones on 800.

 

[K6CDO]

Motorola's trade name for this is Quik Call. It is used to unmute receivers that use tone decoders, or as an audible alert for those who monitor OC Access for the information.

 

[hpycmpr]

This may or may not work. Try using the tone squelch of 136.5. The Q-C may not use the tone thus filtering it. It depends on the system.
Steve

 

[Markb]

That won't work in this case. The QC tones are transmitted with the CTCSS.