Beeps during police incidents

[ckm554]

Hey, whenever I'm listening to the police if there is a serious incident the dispatcher will say "Channel 1 is now 1033" and then every few seconds there will be a sequence of beeps. When everything is "Code 4" the dispatcher will say "Channel 1 is now 1034" and the beeps will stop. It is not the station identifier and it is only used during "major" incidents. Anyone know what I'm hearing?

Chris

 

[WA0CBW]

This is used to alert the users that the channel is being "held" or used for a special situation. It usually tells the other users not to use the channel for regular activities like running a tag. This is activated/deactivated by the dispatcher.

BB

 

[ilgrant]

10-33 in my area is Emergency which may or may not be related.

I have one agency that I listen to that have the beeps as well. It is an indicator to all users that the channel is closed except for Emergency traffic.

 

[N4DES]

It is called a "channel marker" and it is utilized doing a critical incident, like some mentioned above. It's main objective is to alert a radio user that might have just switched on his radio or changed talk-groups/channels that the channel they are listening to is no longer at a normal state of business.

When I was at PBSO (Palm Beach County Sheriff) we implemented it on their old VHF system in the early 90's which was nothing more than a 1KHz tone generator running in a 555 timer that cycled every 10 to 15 seconds. We had the audio level pretty low so it wouldn't give away the officers location, but it was high enough that the typical user would hear it. The dispatcher would activate it along with a flashing blue light as a visual indicator to the communications supervisor.

 

[daveharpe]

In my former home of Louisville KY, they would do this during holdup alarms and officers in trouble.

 

[mmckenna]

aka: restricted traffic.

 

[coolrich55]

I remember when I was a kid watching "cops" a long time ago hearing the beeps in the background. Seemed like it was very popular out on the west coast. First time I heard it in person was when I've been to Las Vegas. I live in New England and I don't know of any department that uses it out here. I'm surprised NYPD doesn't. Seems like when they get a major call the dispatcher just comes over and tells them to clear the air.

 

[KE4ZNR]

Pretty much every medium to large sized city does something like the channel marker that KS4VT mentions above they just have a variety of names/codes/signals for it.
Raleigh PD calls it "securing Raleigh One" and they do it for high priority calls (robberies/shootings/etc) along with foot or car pursuits and once the priority situation is over Dispatch will say "Raleigh one is no longer secured".
Durham PD does the exact same thing as Ral PD but calls it "Signal 20 for Unit Number". Then once the priority situation is over Durham Dispatch will say "Signal 20 clear".
Same exact use just different codes & lingo between the neighboring cities.
Marshall KE4ZNR

 

[N9NRA]

They have that here in WI in the Janesville area, they use it for stuff like gun calls and persuits, In that area it`s referred to as a "closed channel", and when the incident is over they will "open" it back up. Personally i find that to be a good thing, as if there`s something going on and i hear the channel marker (or marker as me and some hams that i know down there call it ) then i`ll give it a listen, if not then i kinda ignore it. N9NRA

 

[RolnCode3]

Used on the west coast too.

 

[N9JIG]

In our system it is called an "EIP" Marker (Emergency in Progress).

IIRC the old 39.xx MHz LA County system used a similar beep system on the base frequencies to let users know mobiles were talking so they didn't get covered. Mobile traffic wasn't repeated regularly so other mobiles wouldn't know the channel was busy.

 

[IredellMon]

Now back when I was working LE... we had no such audio hint that the channel was closed. The dispatcher would just announce it... "CHANNEL CLOSED, 22:13 hours XYZ-1234"
Inevitably before it was reopened someone who had not heard the announcement would call in, "Headquarters, can you copy a few VIN numbers?" LMAO.. it was a sure way to tell who just another guy riding on the taxpayer funded payroll and not doing his job like he should.
The dispatcher would have to bite his/her tongue and calmly reply, "Channel is closed" when what they wanted to say was, "Hey you *#^&@ Dumb ***, can't you pay enough attention to know what a major and dangerous incident in in progress. now STFU until I reopen the channel!"

 

[n1das]

I've heard the beeps on San Diego County's old VHF system...years before they moved to 800MHz. IIRC, it was 9 DTMF "9" digits in rapid succession. It was like it was playing DTMF "999999999".

 

[JoeyC]

And they continued to use that tone until about 2 years ago when they upgraded the SmartZone software on the system. After the upgrade it was reported that while the tone was actively on, units (or dispatcher) radios were not able to talk over the tone, causing missed replies. Its use was scrapped. Interestingly, many dispatchers still ask the officer "do you want the tone?" during emergency situations but they don't activate it. Also, occasionally one will forget and flip it on - however rare.

I miss that thing. It was a great way to be able to scan 20 talkgroups and still know when there was something good going on that warrented a press of the MANUAL button!

 

[W6KRU]

The emergency tone isn't used locally due to the reason stated by Joey above I'm sure. In place of the tone the dispatcher will periodically announce "Emergency traffic for unit#".

I really liked that tone when I used to monitor the Orange Co. sheriffs office. I could turn down the scanners volume at night and the tone would wake me up.

 

[AZScanner]

Long story short, it means "Press the hold/manual button on your scanner, something good is going on."

-AZ