6 FD GND 5 What TG is this?

Ongoing discussions regarding other fire dispatching in San Diego County including Heartland, NorthComm, Monte Vista, etc. Topics about general wildland fire scanning are also welcome here.
mikeybinec
Posts: 6
Joined: Sat Dec 06, 2014 5:32 pm

6 FD GND 5 What TG is this?

Postby mikeybinec » Sat Dec 06, 2014 5:47 pm

Thanks for access

never claimed to be a win96 program expert, but I put a bank in my PRO96 with a Control Channel of 868.4125 for a few of East County Sheriffs TGs. Anyway, it's 5:40pm and there is traffic coming from some folks called 6 FD GND 5.. All I put in was Lemon Grove Dispatch, Santee Dispatch, the TACs for them and a couple of other minor stuff. I closed it so it doesnt scan. Now the people are saying "Burn Blast One" and "get your tail end towards the apartment building" and "change your turn angle". I guess my question is since I did'nt put this TG in how is why I am picking this up?

Am i making sense?

Thanks

800
Posts: 114
Joined: Sun Oct 08, 2006 4:35 pm

Re: 6 FD GND 5 What TG is this?

Postby 800 » Mon Dec 08, 2014 10:20 pm

mikeybinec wrote:Thanks for access

never claimed to be a win96 program expert, but I put a bank in my PRO96 with a Control Channel of 868.4125 for a few of East County Sheriffs TGs. Anyway, it's 5:40pm and there is traffic coming from some folks called 6 FD GND 5.. All I put in was Lemon Grove Dispatch, Santee Dispatch, the TACs for them and a couple of other minor stuff. I closed it so it doesnt scan. Now the people are saying "Burn Blast One" and "get your tail end towards the apartment building" and "change your turn angle". I guess my question is since I did'nt put this TG in how is why I am picking this up?

Am i making sense?

Thanks


Welcome.

6-FGND-5, ID: 2320, is a San Bernardino System 6/7 talkgroup (on the RCS, ID 2320 is 'Travel 10L' in the County Fire group). San Bernardino's System 6/7 and the RCS South Cell each have 4 voice channels that are common, so it sounds to me like you are hearing San Bernardino's system at your location if you are hearing the 6-FGND-5 activity.

I am not conversant in win96 or the PRO96 scanner, so I can't answer your programming configuration question.

mikeybinec
Posts: 6
Joined: Sat Dec 06, 2014 5:32 pm

Re: 6 FD GND 5 What TG is this?

Postby mikeybinec » Fri Dec 12, 2014 7:31 pm

Thanks for reply. Now i,m getting PROBT 1 (ALPHA TAG) on the same channel.. So I'm thinking "it's the Probation Channel". Listening to it carefully, it turns out to be County TAC 1 for Animal Control in North County on 868.4375. I would think the using of the San Diego 800 SmartZone freqs should be limited to San Diego County in regards to to the Berdo

This is kinda cool

Thanks and good holidays

mikeybinec
Posts: 6
Joined: Sat Dec 06, 2014 5:32 pm

Re: 6 FD GND 5 What TG is this?

Postby mikeybinec » Fri Dec 12, 2014 8:09 pm

Now getting an alpha tag called 7 Train 2. It's clearly a Fire dept talkgroup. They are conversing back and forth on 866.1375, 867.3875, 868.6000, 866.6375, 866.9125, 867.6125, 867.4125 . What i find fascinating is that they are using San Diego Control Freqs.

800
Posts: 114
Joined: Sun Oct 08, 2006 4:35 pm

Re: 6 FD GND 5 What TG is this?

Postby 800 » Sat Dec 13, 2014 6:54 pm

What area of San Diego County are you located in?

Frequencies are reused between systems. In 800 MHz, systems are designed to cover the jurisdiction + a few miles outside, to allow for reuse. Systems also have various operating schemes (CTCSS tones for conventional operations, system IDs for trunked systems) to keep the user radios from hearing the adjacent systems sharing the channels.

Southern CA's topography creates all sorts of challenges for system designers / operators. A few years ago San Diego had to change an antenna at one mountain site because the SD signal was clobbering a San Bernardino site's signal on Highway 18 near the 138 interchange just below Crestline.

So while you are hearing San Bernardino area signals, the users down here don't.

Mike_G_D
Posts: 3
Joined: Sun Dec 14, 2014 4:13 pm

Re: 6 FD GND 5 What TG is this?

Postby Mike_G_D » Sun Dec 14, 2014 4:41 pm

I've long had the problem the OP mentioned when I lived in Carlsbad. I could easily hear the San Bernardino system and when they were using the same control channel frequencies as the RCS I would always get their content. Drove me nuts. I have long asked why the scanner designers don't include SYSID filtering in their trunking configuration and never gotten a clear answer - best I got was a vague answer from Don Starr (WINXX software creator and firmware creator/contributor/whatever for the PSR series scanners) that it was too time intensive for a scanner (takes too much time to decode for fast scanning) and/or maybe too computationally intensive for the internal microprocessor.

Don's a smart guy when it comes to software and some basic hardware but, back in the early days of the 500 at least, I got the impression he wasn't really up on his RF knowledge despite his position. I recall trying to get him to understand this problem and his initial reply was something like "Well, the system designers should have made sure their signals stay within the proper boundaries!" I explained that RF doesn't behave itself that precisely no matter how well engineers try to "contain it"! I'm speaking of Don Starr not the "Don" of 800 fame on here, of course;-)!

It always bugged me that both Uniden and GRE could decode and display SYSID but did not actually use it to filter trunk systems! I was really hoping that the PSR500 would use SYSID back when it first became available and was very disappointed when I found it did not.

A pain when dealing with many trunked sites re-using frequencies in relative close geographic proximity. Really confuses hobbyists. A big problem with the federal ELMR stuff too!

-Mike

mikeybinec
Posts: 6
Joined: Sat Dec 06, 2014 5:32 pm

Re: 6 FD GND 5 What TG is this?

Postby mikeybinec » Tue Dec 16, 2014 7:10 pm

^^^^^ GREAT INFORMATION!! I was starting to think that maybe the secondary control channels were being used by outside the county and the signal reached into San Diego County.

I'm in El Cajon btw.

Thanks

mikeybinec
Posts: 6
Joined: Sat Dec 06, 2014 5:32 pm

Re: 6 FD GND 5 What TG is this?

Postby mikeybinec » Sun Dec 28, 2014 3:51 pm

FINALLY!! figured out what's going on and why I was getting these weird t/g alpha tags.. First off, when I was getting stuff like 2 FD GND 7 that's because San Berdu County is split up into six different zones, thus the 2 or 3 or whatever in the beginning of the alpha tag

So this afternoon, I put in a the t/g for Gillespie airport because the FD was staging for a possible crash. So anyway, an alpha tag comes up with a 6 FLOOD 1 or something like that and I'm wondering what this is. So I look up San Berdu in radioreference.com and it turns out that that this 6 FLOOD 1, which is San Berdu's Valley areas County Works Dept. uses the same DEC code as HT GILCMD 4K Command 4K - Gillespie Field Airport --01616

So I wasnt picking up DX scanner traffic, it was just San Berdu alpha tags take precedence over SD county alpha tags for some reason

I live I learn ;)

Mike_G_D
Posts: 3
Joined: Sun Dec 14, 2014 4:13 pm

Re: 6 FD GND 5 What TG is this?

Postby Mike_G_D » Tue Dec 30, 2014 3:52 am

It's not that one system "takes precedence" over another it's that your scanner has locked onto the wrong system so that is what will "take precedence" as far as it is concerned. The scanner is designed such that it will lock onto the strongest and/or best decode-able control channel out of a group of given frequencies (in some cases it chooses the first decent quality CC that comes up in the set of frequencies you have programmed). It doesn't care whether that control channel is what you really want or not in terms of which system you really want to monitor because it is not designed to tell any difference. It is, unfortunately, not designed to distinguish between systems based on anything besides signal strength and frequency. If it could use other criteria such as the SYSID of the system then it could make a "better choice" for you but it cannot (unlike the subscriber radios which do use that information which is why they don't suffer from the same problem - at least not to the extent that a scanner does).

Basically, if you have a system programmed for the SD RCS north zone and one of those CC frequencies also just happens to be part of the SB county system then anytime the scanner starts up and starts looking through the CC frequencies you have in it it will "see" the SB CC signal and may lock onto it first before the "correct" SD CC signal. During deep nulls in the RCS signal (which can happen due to simulcast phasing issues depending on where you are located) the scanner can also often "leave" the "correct" CC and "go looking" when you really don't want it to and "find" and lock on to the incorrect CC. In which case you either will get no traffic or "weird" traffic on "strange" talk groups. If some obscure talk group in the RCS system uses the same number as one of the ones in the SB setup then you will hear whatever traffic is on that talk group. Labels are just for humans - the numerical codes the labels are attached to matter to the scanners.

About the only thing you, as a scanner user, can do is to limit the actual programmed CC frequency list as much as possible. In the case of the RCS, it is often best to just program one zone per system in your scanner (just the North, for example, when listening to north county stuff) and then only the primary and alternate CC's for that zone. Don't program all of the CC's for all of the zones together. For the most part, you can leave out the fill in stuff and just concentrate on the major zones (North, South, East, and Northeast). Just pick the closest one to you and program only the CC frequencies for that zone. Then you minimize the chances of having the scanner inadvertently locking onto a wrong system or site.

-Mike


Return to “Other Cities Fire Scanning”

Who is online

Users browsing this forum: No registered users and 2 guests