Dispatch-to-Dispatcher Communications

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Sac916

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Seeking information on Dispatcher-to-Dispatcher communications -----
(often used for immediate communication, BOLOs and advisements in a region)

I'm looking for examples on how Dispatchers communicate with each other in a region.

For example;
Placer County utilizes Law Net (CLERS) at Wolf Mountain
Sacramento County utilizes a hardwire Hot Line (landline intercom)

I need this information for a study and hope those in other counties can shed light on how departments handle Dispatcher-to-Dispatcher (only) communications.

I've gone through the database, looking at larger metro areas - but I really don't understand some of the local terminology, so I don't know if they're talking about a "Hot Line" or just a Mutual Aid frequency.

My understanding is that most agencies utilize either CLERS or a conventional freq.

I would like those in other counties to chime in and clue me in on whether it's Conventional freq, microwave, landline or other ....


Additionally, if there are any departments with a Trunked Radio System, I'd like to know how they handle Dispatcher-to-Dispatcher communications with those outside the TRS.
 
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K6CDO

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In San Diego County, the agencies use dedicated Fire and Law intercom talkgroups on the RCS. This includes some non-RCS agencies like San Diego PD and Fire. Others outside the RCS are reached via telephone.
 

marcp90

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Kirk

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I've never heard CLERS used in SLO County, other than tests by OES. There is a simulcast system called "Red" (460.050) that is an all agency channel. You'll hear BOLs announced as "Attention all listening units and stations." But it's not just dispatcher to dispatcher, as pursuits by agencies other than CHP are often moved here. The system covers both SLO and Santa Barbara counties, but I'm not sure I've ever heard an agency south of Santa Maria using it. But it is used by SLOSO and all of the SLO County police agencies.

I'd imagine other stuff is done by phone.

No such network exists for fire, so I'm guessing that's all by phone as well.
 

jlanfn

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San Bernardino County uses what they call over the radio a "law intercom." It doesn't correspond to any radio channel or talkgroup I know, so I always assumed it must have been a landline intercom.
 

kma371

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Contra Costa Co agencies did utilize CLERS for countywide BOLOs. With the EBRCS system in place, I don't know if that's still active.

San Joaquin Co does not use any form of radio communication between agencies, only telephone.
 

f40ph

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San Bernardino Co uses a "hot line" / landline for the Fire Intercom between agencies including USFS and CalFire.
 

zz0468

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San Bernardino Co uses a "hot line" / landline for the Fire Intercom between agencies including USFS and CalFire.
Law and Fire are intercoms that appear in the consoles like conventional radio channels, but are carried by microwave and leased line circuits to the appropriate agencies.

Riverside County has similar intercoms.

These intercoms are what's referred to as a "hoot and holler" circuit. There is no dialing, just select the intercom channel and call the agency you want. If they're listening and paying attention, they'll hear and answer. There could be two dozen or more agencies all listening to it at the same time.
 

Kingscup

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My limited experience has been what is called a "ring down" line (landline). A dispatcher selects an agency by pressing a button on the console and it automatically rings at the other dispatch center.
 

BlueZebra

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Probably the most extensive network, at least in terms of area covered, is Cal Fire's microwave Intercom. There a No Ops Intercom, and a South Ops Intercom, with all CalFire Units, and USFS Dispatch Centers on the appropriate Intercom, as well as North and South Ops, and Sacramento HQ. Lots of traffic there, primarily about aircraft ordering, but also informational broadcasts.
 

Sac916

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Law and Fire are intercoms that appear in the consoles like conventional radio channels, but are carried by microwave and leased line circuits to the appropriate agencies.

Riverside County has similar intercoms.

These intercoms are what's referred to as a "hoot and holler" circuit. There is no dialing, just select the intercom channel and call the agency you want. If they're listening and paying attention, they'll hear and answer. There could be two dozen or more agencies all listening to it at the same time.
Is this the Cisco product? If so, can you PM if you have any contact info for end user/technician familiar with the installation.
 

zz0468

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Is this the Cisco product? If so, can you PM if you have any contact info for end user/technician familiar with the installation.
No, it's not a Cisco product. These types of circuits are called conference bridges and they take various forms. Tellabs sells analog conference bridge hardware, and they are also a function of digital cross connect switches (DACS). A DACS is a $200,000 piece of network hardware found in telco central offices and large private networks.

The law and fire intercoms in Riverside and San Bernardino counties are a combination of hardware and DACS conference bridges interconnected by microwave and leased lines.
 
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SCPD

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All the dispatch centers in Inyo and Mono Counties have a circuit on the state's microwave system and it is called the "Hotline." There aren't all that many dispatch centers, one of each county, the USFS/BLM Owens Valley Iinteragency Dispatch Center, the city of Bishop, the CHP, Caltrans and the CDF comm center in San Bernardino. A 400 MHz link to the Mammoth PD used to exist as Mammoth is in a place where microwave would be very expensive to provide. When the link existed I used to listen to it. They used it to relay hot calls to each other, update the other agencies on road conditions and when there were a lot of smokes popping up during thunderstorms both counties, who get the majority of the 911 calls, needed to know if a wildland fire agency knew about particular fires.

CLERS in the eastern Sierra is only provided on the microwave network . There have never been any mountaintop networks on CLERS here.
 
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SCPD

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Probably the most extensive network, at least in terms of area covered, is Cal Fire's microwave Intercom. There a No Ops Intercom, and a South Ops Intercom, with all CalFire Units, and USFS Dispatch Centers on the appropriate Intercom, as well as North and South Ops, and Sacramento HQ. Lots of traffic there, primarily about aircraft ordering, but also informational broadcasts.
Both networks used to use VHF low, VHF high and UHF to link key mountain tops. I used to be able to hear both the south ops net off Silver Peak near Bishop and the north ops net off Mt. Rose near Reno. The latter used VHF low and that is the only reason I could copy it, at least most of the time. Propagation was not always cooperative for listening to it with the worst signal being in summer, just the time I wanted to listen to it.

It is much easier to maintain the microwave network than maintaining a couple of dozen mountain top links. Some of those mountain tops did not have good, year long access. Too bad for scanner listeners however. When I used to travel to L.A. in the summer (rare) I had a great copy off Santiago Peak, which was used to provide coverage to the San Berdo, Angeles and south ops centers. The most common traffic had to do with the assignment of aircraft to different jurisdictions. Automatic mutual aid dispatches used the net as well.
 

zz0468

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It is much easier to maintain the microwave network than maintaining a couple of dozen mountain top links. Some of those mountain tops did not have good, year long access.
Except those microwave links live in a lot of those same high mountaintops. The thing that makes life easier is that the microwave radios are all hot standby protected, so it's possible to live through a winter without a failure. If things were built right.

The most common traffic had to do with the assignment of aircraft to different jurisdictions.
I still hear traffic that sounds like that on ANF and SBD Forest Nets.
 

davedaver1

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Seeking information on Dispatcher-to-Dispatcher communications -----
(often used for immediate communication, BOLOs and advisements in a region)

I'm looking for examples on how Dispatchers communicate with each other in a region..
So, the correct answer is - everyone uses something different.

That's the joke about interoperability. Everyone has different connectivity needs (adjacent city, county, other regional authorities, blah, blah. Wireline has always been preferable for point-to-point comms with radio as a backup.
 

zz0468

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Wireline has always been preferable for point-to-point comms with radio as a backup.
Not in my experience. Wireline is always looked at as a last resort to get something economically done. Microwave is frequently the preferred method for handling point-to-point circuits, but it's not always economical to run a link to a dispatch center just for an intercom.

I HAVE seen that done, however. There are microwave links between several Southern California counties just for the purposes of handling interoperability communications. Land lines are a distant second choice because they are notoriously unreliable and difficult to get repaired correctly.
 

inigo88

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Ant,

Marin county uses a talkgroup on the MERA trunked radio system called Blue Command, formerly called "PD MAC" (Police Dept Mutual Aid Channel) for both dispatcher-to-dispatcher comms and BOLs/APBs (multiselected with the "PD APB" talkgroup in those cases). When countywide law enforcement was on lowband prior to the switch to trunking, a lowband repeater frequency on 39.52 MHz called "Control 2" was used (much like SLO's UHF countywide law common frequency already).

As K6CDO already said, San Diego County uses very similar talkgroups but split between law enforcement and fire, called "LAW CC" and "FIRE CC" (comm center-to-comm center).

The Orange County Countywide Coordinated Communications System (CCCS) has a talkgroup called "DSP-DSP" (dispatcher-to-dispatcher) for the same purpose.

As you can see from my examples, many of the dispatcher-to-dispatcher channels were or still are shared use for both comm center interoperability (between dispatchers) and as a countywide law common for officers. This can no doubt create problems when the simultaneous need for both arises.
 

kf6ewpdan

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Butte County uses a lowband repeater. Its mainly used for EMS to let know Cal Fire or a few other fire departments know that medics are responding, but every PSAP/dispatch center has lowband. I have never heard traffic on the CLERS UHF repeater we have in Butte except for state testing. I know the dispatch centers have it in their consoles too.
 

KMA367

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Seeking information on Dispatcher-to-Dispatcher communications -----
(often used for immediate communication, BOLOs and advisements in a region)

I'm looking for examples on how Dispatchers communicate with each other in a region.

For example;
Placer County utilizes Law Net (CLERS) at Wolf Mountain
I've lived/worked in several parts of the state over the decades, and that foothill-counties CLERS "Net 4" (155.07R/159.03m) was used a lot - as in daily - in the early 80s when I was at Grass Valley PD. They'd do BOLOs, relay hot calls to the correct agency, all kinds of stuff. Sacto CHP seemed to act as the control station, but anybody might come up with a report or request. It's the only one I've ever been around that got much use at all.

In the 60s-70s, the Santiago (Lukens?) 158.79R "Net 1" was quiet except I believe it was Corona PD who used to call Orange County to run warrant checks at least once or twice a week. Here on the North Coast and in the Shasta-Siskiyou area, "Net 5" 155.07R has been absolutely dead for other than annual-seeming radio checks since I moved north 26 years ago.

Those Net numbers may be obsolete by now for all I know.
 
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