Los Angeles Co.Sheriff

[rananthony04]

Is/was anyone monitoring LASO (Lakewood Dispatch-483.1375) today (7-25 around 1030 hrs.)? If so, what kind of testing (if thats what is was) requires the use of beeps, and high to middle to low(and vise versa) pitched tones? I have never heard of these kinds of tones on the scanner. Kind of reminds me of grade school days, where they made you take those hearing tests in that trailer equipped with several stations. You then had to press a button everytime you heard a tone played in the earphones. Not sure what channel Lakewood is patched to for dispatch, as I turned off the scanner.
Now that I think about it, I know that some testing has been going on these past couple of weeks. Most if not all consisted of removal of the busy tone. I was listening one day and just happen to look down at the scanner display and noticed it was a LASO channel(I thought dispatch forgot to release the patch, as this does happen-rarely) but after a few minutes, I heard dispatch tell the deputy's that testing was complete and the patch was no longer in use. This happened alot at night. I've asked a few deputy's already and A. They look at me as if I do not know what I am talking about, and B. They know what I am talking about, but have no info regarding a sysytem upgrade of any kind. Anyone know of anything?

regards,
-Robert Anthony

 

[Uplink]

Sounds like you heard a sweep test, used to check frequency response of a piece of gear across the audio spectrum.

 

[rananthony04]

These might sound like dumb questions. What is the purpose of the sweep test? How often is it done? Does it indicate a sysem change?

-Robert A.

 

[rananthony04]

Additional on LA Sheriff..

Does anyone monitor LASO around 0300hrs on any givin day of the week? This is around the time that I hear the most annoying morse-code sounding beeps (long, long, short, etc...) OR long, loud tones, sounds like the kind of tone that LAPD uses (the 3 short alerting tone) before dispatching a call. I even hear them on the Mutual Aid channels too. Why do they do this?

-Robert

 

[Uplink]

Does anyone monitor LASO around 0300hrs on any givin day of the week? This is around the time that I hear the most annoying morse-code sounding beeps (long, long, short, etc...) OR long, loud tones, sounds like the kind of tone that LAPD uses (the 3 short alerting tone) before dispatching a call. I even hear them on the Mutual Aid channels too. Why do they do this?

-Robert

They do this every morning as a system test on every channel in the system. They have a huge network of repeaters simulcasting from mountain tops all over the county. They have remote test sets that send tones to the receivers make sure all of their receivers and voters are working. Yes, it is annoying, I'm glad I'm not a Sheriff on that shift.

 

[rananthony04]

Yes, it is annoying, I'm glad I'm not a Sheriff on that shift.

NO KIDDING!

 

[selgaran]

But I'd be glad to be using a radio system where they go to that much effort to make sure it is working well all the time...

 

[Radio_Lady]

They do this every morning as a system test on every channel in the system... Yes, it is annoying, I'm glad I'm not a Sheriff on that shift.

It is annoying, isn't it? Before we went to digital, LAPD used to do it every morning too, and it drove the ofcrs crazy. At that time all 18 dispatch and tactical channels used multi-site simulcast, and this made sure all of the TX sites were in sync. At least theoretically. It was done automatically, one frequency at a time, and we had no control over it. If there was an emergency at the time, we'd have to switch to a tac frequency for it. Fortunately that didn't happen very often.

With the current digital system, the 54 dispatch, fallback ("simplex"), and bureau tac frequencies each use just one TX site at a time. AFAIK only the seven citywide tac frequencies use multi-site synchronized simulcast, to give them better coverage both within the city and a out a ways, like for pursuits. I haven't noticed any synchronization tones on those freqs, but I haven't really paid any attention. It wouldn't surprise me if some of the specialized divisions' frequencies use simulcast too, but I don't know.

 

[rananthony04]

When you mention the "seven citywide tac frequencies", I am assuming you mean CW tac 1-6,(channels 44-49), and tac 7 on channel 177(what is the deal with that anyways?(ch.1`77)) As far as any synchronization is concerned, I have heard nothing that resembles such-on any of the LAPD channels. Regarding LA Sheriff, it's too bad bad they do those annoying tests, they are one of my favorite agencies to listen to, until about 0300. One more thing about the LA Sheriff (Radio Lady, maybe you can help me out with this), why are the deputy's told to 10-22 their involvment in a pursuit?(after initiation) For those of us that live in the LA/OC area, when was the last time you seen LASO initiate and continue a pursuit? Not since they were involved in that really nasty shootout that injured some deputys a while back. thats the last major one that I can remember.

-Robert