San Diego City 700MHz System

ScanFanEd

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Hope this does not sound like too dumb of a question, but can anyone tell me how SDPD, being on their 700MHz System, accesses some of the RCS TG's, such as LE STAC 1, LE E TAC 1 and other mutual aid TG's? Yesterday I heard an event that Chula Vista PD had working at the extreme southern end of their city on LE STAC 1 (patched to their CVPD Disp 2) and there were a couple of SDPD Southern units assisting as well on LE STAC 1. I am just wondering if there is a patch between the SDPD 700MHz system and the RCS NextGen MA TG's, or if SDPD units actually have RCS NextGen zones programmed into their radios.

Thanks!
 

Elpablo

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From my listening experience, usually, the SDPD dispatcher will direct them to a specific SDPD tac that the dispatcher will then patch to LE S TAC or CMD. It seems like dispatch does the patching vs. the officer trying to find LE S TAC or whichever RCS channel in their radio (which I do believe is programmed into their radio but is cumbersome to find). In some cases, SDPD will switch to their Police Patch talkgroup, where patching is done with the RCS to work with other agencies. Hope this helps.
 

ScanFanEd

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Thanks! That makes sense. I did hear the CVPD Dispatcher advise the SDPD Southern units that their agency would be patching them to a talkgroup, however I missed which TG it was. Based on what you mentioned, it was likely one of the SDPD tac channels.

Thanks again!
 

inigo88

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Back in the old days, radios on the two systems couldn't (or wouldn't) be programmed to talk to each other. As a result SDPD and county law enforcement dispatchers would create patches between talkgroups on the two systems. Some pursuit on SDPD Southern Dispatch 1 could be patched to LE South Command for example. When patching an RCS talkgroup incident to the city system, traffic would always be patched to one SDPD talkgroup creatively named "PATCH", and officers would have to "switch to patch" to hear the RCS traffic.

Nowadays the city system talkgroups and RCS talkgroups are just two zones in the same radio, so the officer can easily switch over if they wish. The downside to this is that the radio will only priority scan talkgroups from the trunking system belonging to the talkgroup it's currently on, which a lot of radio users don't realize. So if I'm an SDPD officer on Mid City Dispatch 1 and I switch to LE South Tac 2, my radio will stop scanning any of the SDPD channels and I won't hear my dispatcher calling me until I switch back to a talkgroup belonging to the city system (or keep a second radio nearby on a city system talkgroup). It's worth noting newer APX radios do support a "multi-system scan" option that fixes this limitation, but I'm not sure if it's programmed or not.

Training and dispatch center procedures haven't necessarily caught up to the fact that both systems are programmed in the radios though either, so city and county dispatchers will still work together to create patches between the city system and RCS, largely out of convenience for the officers who may already have their hands full (imagine fumbling with changing zones on the radio in the middle of a high speed chase). SDPD "PATCH" still gets used, but if they patch SDPD "PATCH" to RCS "LE S CMD", it's a toss up on whether the officers switch to PATCH or just go directly to the RCS talkgroup since they have both programmed. The radio programming in the LE helicopters has always been excellent, so ABLE/ASTREA will almost always affiliate to the original talkgroup an incident is occurring on and not a patch, and can talk to conventional users like CHP on VHF low band, Cal Fire on VHF, etc.

Long story short, some really smart people worked on communications interoperability in San Diego/Imperial counties over the last several decades (some who used to participate on this forum even), and in my opinion it's very well thought out.
 

Anderegg

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The county, maybe the city also, program their radios so the user isn't accustomed to leaving their zone during their shift. When they have to go searching through zones, they probably feel like someone who has never held a gun before attempting to clear a jammed round out of the chamber of an AR15. Fire zones are well thought out with the DIR channels in every zone.

Paul
 

inigo88

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Having been an RCS user in the past, I think their law fleetmap is very well thought out. What you touch on is in my opinion more a symptom of the night and day difference between how fire agencies and law enforcement agencies are trained in radio use, and how much better fire agencies are at mutual aid and ICS. And I’m not picking on cops either, it’s just a byproduct of how ingrained into the job mututal aid and interop is on the fire side, where as LEOs rarely have to leave their home zone in their radio. This is strictly applicable to patrol division LEOs as well, who likely spend their whole shift on a couple radio channels (“D1”, “D2” and “Inquiry” haha). The notable exceptions on the law enforcement side are the specialized units like air (ABLE/ASTREA), K9, investigations, etc who need to be fluent in their radio fleetmaps to be able to respond to incidents all over their city and do mutual aid to surrounding agencies as well. And I actually think the ABLE/ASTREA TFOs are exceptional at this, because it’s a pretty complicated county.
 

jmarshl

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I totally agree with inigo88 and I believe law enforcement could benefit from more radio training.
 

ScanFanEd

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Back in the old days, radios on the two systems couldn't (or wouldn't) be programmed to talk to each other. As a result SDPD and county law enforcement dispatchers would create patches between talkgroups on the two systems. Some pursuit on SDPD Southern Dispatch 1 could be patched to LE South Command for example. When patching an RCS talkgroup incident to the city system, traffic would always be patched to one SDPD talkgroup creatively named "PATCH", and officers would have to "switch to patch" to hear the RCS traffic.

Nowadays the city system talkgroups and RCS talkgroups are just two zones in the same radio, so the officer can easily switch over if they wish. The downside to this is that the radio will only priority scan talkgroups from the trunking system belonging to the talkgroup it's currently on, which a lot of radio users don't realize. So if I'm an SDPD officer on Mid City Dispatch 1 and I switch to LE South Tac 2, my radio will stop scanning any of the SDPD channels and I won't hear my dispatcher calling me until I switch back to a talkgroup belonging to the city system (or keep a second radio nearby on a city system talkgroup). It's worth noting newer APX radios do support a "multi-system scan" option that fixes this limitation, but I'm not sure if it's programmed or not.

Training and dispatch center procedures haven't necessarily caught up to the fact that both systems are programmed in the radios though either, so city and county dispatchers will still work together to create patches between the city system and RCS, largely out of convenience for the officers who may already have their hands full (imagine fumbling with changing zones on the radio in the middle of a high speed chase). SDPD "PATCH" still gets used, but if they patch SDPD "PATCH" to RCS "LE S CMD", it's a toss up on whether the officers switch to PATCH or just go directly to the RCS talkgroup since they have both programmed. The radio programming in the LE helicopters has always been excellent, so ABLE/ASTREA will almost always affiliate to the original talkgroup an incident is occurring on and not a patch, and can talk to conventional users like CHP on VHF low band, Cal Fire on VHF, etc.

Long story short, some really smart people worked on communications interoperability in San Diego/Imperial counties over the last several decades (some who used to participate on this forum even), and in my opinion it's very well thought out.
Great overview, inigo88!

Would you, or anyone else, know how SDPD mobiles and portables are programmed as far as zones? I am wondering if they just have the two zones for the two systems (SD City 700 and RCS), or if they have additional zones that are dedicated to individual agencies, mutual aid and such?
 

inigo88

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Great overview, inigo88!

Would you, or anyone else, know how SDPD mobiles and portables are programmed as far as zones? I am wondering if they just have the two zones for the two systems (SD City 700 and RCS), or if they have additional zones that are dedicated to individual agencies, mutual aid and such?
I’ve never seen SDPD, but RCS law is a combination of different RCS LE agencies split up by zone, a zone or two dedicated to SDPD on the city system, 800 MHz conventional statewide mutual aid channels and state parks, RCS conventional (“CARS”), RCS law mutual aid (LE N CMD, etc), county mutual aid (SDCoCall, County Tacs, etc). It’s very robust.

The helicopters are even better because they’ve got all that, plus CHP on lowband, plus federal law enforcement.

I do know that the SD city radios have some city specific conventional channels, such as “Lifeguard Conventional”, which they’ve been using recently for cliff rescues in Sunset Cliffs in areas of spotty trunking system coverage. There are likely some SD city law enforcement and fire conventional channels waiting to be figured out as well. :)
 

es93546

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Having been an RCS user in the past, I think their law fleetmap is very well thought out. What you touch on is in my opinion more a symptom of the night and day difference between how fire agencies and law enforcement agencies are trained in radio use, and how much better fire agencies are at mutual aid and ICS. And I’m not picking on cops either, it’s just a byproduct of how ingrained into the job mututal aid and interop is on the fire side, where as LEOs rarely have to leave their home zone in their radio. This is strictly applicable to patrol division LEOs as well, who likely spend their whole shift on a couple radio channels (“D1”, “D2” and “Inquiry” haha). The notable exceptions on the law enforcement side are the specialized units like air (ABLE/ASTREA), K9, investigations, etc who need to be fluent in their radio fleetmaps to be able to respond to incidents all over their city and do mutual aid to surrounding agencies as well. And I actually think the ABLE/ASTREA TFOs are exceptional at this, because it’s a pretty complicated county.
I have the same observations of people in the fire service being far more radio savvy than people in law enforcement. It is necessity being the mother of invention as the fire service regularly crosses jurisdictional boundaries even in day to day situations, some stations more than others of course. Wildland fire assignments require more radio savvy, they can't always depend on getting their radios cloned before joining in. Having crew boss on my list of red card positions took me to the point of having a BK cloning cable in both my red pack (long term assignment gear) and in the glove compartment of my green truck. My handheld always had the little red button to be able to program attached. Sometimes you could get sent to a fire that had been going for a few days, but arrive when it was blowing up and threatening lots of structures. I would roll into camp, get a shift plan (IAP, Incident Action Plan), tear out the comm plan, give a crew member the manifest to sign in, get our assignment and then program my radio first, then do the quick job of cloning all the others. Sometimes I would have a crew member or if I had a crew boss trainee with me, they would clone while I drove. I think every hotshot crew did this as well. Most R5 (CA) engine crews did the same. The whole reprogram ad hoc thing didn't seem to penetrate in a lot of some other regions, but did catch on in R3 (AZ NM) when R5 people who were "burned out" transferred there for their last 5-10 years before retirement. You just don't find that level of knowledge and experience in most law enforcement officers.

Firefighters have to be heads up all the time because inattention costs lives. However, the percentage of people we dealt with that wanted to kill us was miniscule compared to what LEO's face. Their every move might become basis for a significant court case and they have about 12 things to keep track of when they pull a vehicle over or even worse respond to a domestic or unknown trouble call. They don't have time to think about radio frequencies and the like. In firefighting it is a big part of LCES and we have to know it well cause of it. For a cop, it's how do I talk to dispatch, what is the tactical and how do I talk with the helos. Many CHP officers I've known since the agency equipped officers with the 700 MHz extenders can be fairly familiar with radio systems since they have access to almost everything. They tend to get sent to distant places as they transfer around and when the CHP provides a large mutual aid presence in the state more often as well, so they have more radio savvy.
 

disp10

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Hearing what sounds like a PD dispatcher speaking to a trainee dispatcher on TG 19. Somewhat interesting chatter for the uninitiated who can get a glimpse into the "why" behind some of the things they do.
 

disp10

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Reprogramming of Fire / EMS radios began this month. It is estimated to take at least 3 months. With this reprogramming you will slowly see users migrating full time to the 700 mhz system.
 

Anderegg

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Was hearing a fire engine on 7E in digital last night...I was confiused, almost sent them an email to confirm when they plan to transition. My SDFD zone is the only analog trunking zone left in my scanners.

Paul
 

Elpablo

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Hearing what sounds like a PD dispatcher speaking to a trainee dispatcher on TG 19. Somewhat interesting chatter for the uninitiated who can get a glimpse into the "why" behind some of the things they do.
I agree and find myself listing to this Dispatch Training talkgroup whenever I find it active. They use to do this on one of the unused dispatch talkgroups but they with migration to the 700 Mhz system, they have a dedicated TG. Very cool insight on what's going on in the dispatcher's head during the performance of their job. Makes me have even more respect for what they do.
 

SDBud

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I updated my 700 stuff for the City, and have it running on a separate radio form the 800, with just FD on it. Hearing ALS med traffic, but NOTHING else, over about 2 hours. Plenty of disp., medical and t/c traffic on the 800. Will keep both running in the daytime just to compare. NOW on what is in the database as the FD Emergency TG, I'm getting PD MidCity Disp. (TG 321, mentioned Utah St.)
 

SDBud

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Just now, on FD Admin.. E24, I just had the radio reprogrammed and now having problems with it. 10-7 to the radio shop.
 

Anderegg

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Putting a 700MHz trunking input frequencies scanlist into my SDS scanner...does anyone know if the inputs have a NAC? I think I have seen the output NAC for the SD 700 system as 370 I think, but not sure for inputs. On digital only SDS programing this shouldn't be an issue, no interference right? On the old SD system, I used the PL of 136.5hz since it was close enough to the connect tone to work as a squelch/interference control.

On the output frequencies, anyone know the "hang time" for the repeaters? I am seeing them drop signal, but conversations will still "catch" a couple of seconds later on the same frequency. Setting delay for a output frequency scanlist.

Paul
 
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