Channel Marker tones on Colorado DTRS

[dw2872]

"Channel Marker" tones are the beeps you might hear on some law enforcement agency talk groups or channels when they want to "hold the air" due to an emergency incident.

Steve and I just had a conversation about it and we figured out a few key pieces of info about some of the agencies that use it.

All of the "beeps" are half a second long.


- Colorado Springs PD uses an interval of 10 seconds between tones.

- Douglas County SO uses an interval of 15 seconds between tones.

- Jefferson County SO uses an interval of 20 seconds between tones.


All intervals are from the start of one tone to the start of the next tone.


Some are saying that these tones are contributing to congestion on DTRS and causing "busies" on some sites. I think that may be an assumption and not from actual data. Every incident that I have heard where those tones were employed are also accompanied by a lot more transmissions of talking about the incident, so it is strange that one would attribute the "busies" to the tones and not the fact they are talking a lot more during the emergency.


QUESTION: Is anyone aware of any other Colorado agency that uses them? Their must be more than just these three.

 

[GrayJeep]

QUESTION: Is anyone aware of any other Colorado agency that uses them? Their must be more than just these three.

I have NOT heard them for- City of Ft. Collins (before encryption), Larimer County, City of Loveland, City of Longmont, Weld County or CSP for 3A and 3C.

I've been listening a long time (20 + years) and haven't heard what you described ever.

 

[dw2872]

I have NOT heard them for- City of Ft. Collins (before encryption), Larimer County, City of Loveland, City of Longmont, Weld County or CSP for 3A and 3C.

I've been listening a long time (20 + years) and haven't heard what you described ever.

OK. Thanks for ruling out those agencies! I don't think CSP uses it at all anywhere in the state.

 

[natedawg1604]

I'm pretty sure (99% sure) JeffCo and DougCo just started using emergency tones within the last few months.

 

[dw2872]

I'm pretty sure (99% sure) JeffCo and DougCo just started using emergency tones within the last few months.

Yep. Steve mentioned they recently upgraded consoles, so that makes sense. And also that El Paso County (Zone-4) may play by their own rules.

Colorado Springs PD has been using those channel marker tones for many years, so theirs has nothing to do with consoles. CSPD tones sound (and look on a spectrum analyzer) exactly the same as the ones in DougCo and Jeffco. Also, CSPD has 4 dispatch TGs and they are used on all four, depending which division the incident is happening.

 

[Spitfire8520]

Yep. Steve mentioned they recently upgraded consoles, so that makes sense. And also that El Paso County (Zone-4) may play by their own rules.

Colorado Springs PD has been using those channel marker tones for many years, so theirs has nothing to do with consoles. CSPD tones sound (and look on a spectrum analyzer) exactly the same as the ones in DougCo and Jeffco. Also, CSPD has 4 dispatch TGs and they are used on all four, depending which division the incident is happening.

I would be surprised if the tones weren't the same. It is a product offered directly by Motorola for all of their dispatch consoles, just a mouse click away. The potential users would be statewide on any of the Motorola systems. It would largely be up to SOP on how it would be used, if at all. Other than the agencies listed, I don't know of any others that use them.

As for system busies, I don't imagine that they do much in terms of loading. Very short voice grants that most sites should handle well. The only time I would imagine starting to hit busies is assigning a large amount of talkgroups to an incident (which should be past the point of priority traffic) or large multi-agency incidents in a rural area. At that point, they really should be using some type of tactical or interoperable talkgroup/frequency instead of one's primary dispatch.