When i monitor LA Sheriff there are some annoying beeps at the end of some of the transmissions is there anyway to get rid of the tone is that tone out?
LA Sheriff annoying beeps at end of transmission
- Thread starter mattfox27
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No, what you are hearing is the "channel busy" tone.
LASD "trunks" dispatchers (instead of channels) in the current system, and does not normally repeat the mobile units.
LASD "trunks" dispatchers (instead of channels) in the current system, and does not normally repeat the mobile units.
OK, you'll need to explain this one to me. Even when they were on the 39 MHz system, LASO had the annoying "beep" which just told anyone listening that a deputy was broadcasting from his patrol unit. That carried over to the current 480 MHz system.
You say that LASO "trunks" dispatchers. Now I know that they tend to have one dispatcher handling multiple stations. That's why I hear Lomita/Santa Clarita/West Hollywood, etc. broadcasting on the Norwalk frequency.
My question is, what does this "trunking" of dispatchers have to do with the annoying "beeping?"
Dave
KA6TJF
OK i wasn't sure what tone out was i thought maybe it would start scanning again if it heard that annoying beeping tone...So thats normal
As far as I know, the beeping is "normal." Now, if you're close enough, you can always program the mobile frequency (found on the RR database) and try to listen to the deputy as he makes his transmission. When I lived in unincorporated Whittier many years ago, I would try to listen to the Norwalk units while they broadcast on the mobile frequency and then toggle back to the base frequency for the reply. Now that I live in Orange County, I just live with the "beeping" since I'm too far away to receive the mobile unit. Of course, the beeping drives me batty, so that's why I rarely listen to LASO anymore.
What I don't understand is why the gent in San Diego brought up the "trunking" of dispatch frequencies. I don't think that has anything to do with the beeping, but maybe I'm wrong.
Dave
KA6TJF
Go back to the way LASD handles calls for service. A resident of Altadena (as an example) calls 9-1-1. That call is answered at the local LASD station (Altadena Station, in this case). The call is entered into their CAD system and sent to the assigned cars and to an available operator at the Sheriff's Communications Center (SCC). The call is voiced on the local dispatch channel (DISP 1) by the SCC operator, who then moves on to the next call - which may be a call from Newhall, to be voiced on DISP 5.
Field units calling into SCC just key the transmitter when they don't her the Channel Busy tones, and make their transmission (and give their unit ID at the start and end of each transmission in case no dispatcher hears the start of the call). The incoming mobile signal is routed to the first available SCC operator, who gets audio in his/her headset along with the working calls on that dispatch channel.
This is why you hear so many different SCC voices when monitoring a single LASD dispatch channel.
LASD went to this system during the 39 MHz days in the 1970s. With the move to 480, only the radio circuits feeding the switching matrix changed. Since there is no dedicated SCC operator monitoring each DISP channel, LASD does not as a matter of routine enable the relay function of the channels, saving that for times where a live SCC operator is actively working the channel. The beeping tells the firld units that another unit is transmitting on the uplink side of the half-duplex channel pair.
Think of it as LASD operating like CHP has been before the current repeater upgrades, without the CHP vehicle radios also monitoring the car-station frequency.
Don
Don, thanks for the explanation. And I don't mean to be offensive, but this is just too complicated for simple little ol me. I got my BA from Cal State Fullerton instead of UCI, UCLA, UC Berkeley, et. al. and it definitely shows! How I long for 1968 and that resonant female voice dispatching 1-Adam-12 on KMA 367.
Dave
KA6TJF
10-22
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Well, not quite. Although the station takes the initial call and inputs it into the CAD the RTO's don't round-robin from call to call. A RTO is assigned frequencies and handles those for continuity. Othewrwise, one RTO taking the next radio call in the queue would have little idea except for the comments in the CAD about a call. When the same RTO keeps the frequency s/he is more likely to remember that went 51-Tom-2 went 10-97 (on scene) 3 ago and cannot be reacched by radio. During a major call the RTO is left on that frequency (unless relieved by a supervisor) and their other frequencies are assigned to another RTO. RTO's also tend to be assigned the same group of frequencies daily because it helps being familiar with the areas of service. Otherwise, a CAD system could voice dispatch without the need for a real person. Sometimes the sub-station self-dispatches.
No problem, Dave. I would be in the same position as you except for my volunteer work with L.A. County Disaster Communications Service in the SCC building from 1977 to 1984, and my work in Public Safety Comms for the state from 1984 to 2006.
Don
Are you saying that LASO deputies don't carry portables on their utility belts? What happens if a deputy goes into foot pursuit?
Dave
KA6TJF
P.S. When I was a newspaper reporter back in the mid-80s, I went on a ride-a-long with an LASO deputy patrolling La Habra Heights. He showed me his Realistic four-channel pocket scanner that he would take with him when he was outside his squad car. Even then I was a little shocked that the deputy wasn't issued a portable. I'd be more shocked if they're still not issued portables 25 years later.
I shouldn't put words in his/her keyboard, but what he said was
"Cannot be reached by radio" is entirely different from not carrying a radio, and in the officer-safety context (where officers and dispatchers live) is a much more emergent and ominous scenario. Having BTDT, I took "10-22" to be implying that the unit was for some reason unable to answer the dispatcher, and possibly needing assistance.
We do carry portables, currently I'm personally issued a Motorola XTS-5000. Although we didn't start carrying portables regularly until about 1990. 10-22 provided a very good description to correct errors in k6's post. Although K6 was almost there. One thing is that when RTO's drop channels do to an emergency those other channels are not automatically picked up by another RTO. The channel if dormant may stay unassigned until needed, such as a call that needs to be voiced (not all calls are), a deputy in the field keys his mic. or a deputy running something on his MDT/MDC gets a hit that needs to be status checked. In that case the channel is then assigned to the least busy RTO, and yes there is a computer that checks their call load. It will also sometimes readjust RTO's to keep them from getting to busy, but will not move an active channel from an RTO. This will also be done sometimes from the floor if an RTO has something they are trying to stay on top of they may ask for one of their partners to pick up a channel from them.
Starman918
Member
Back in the day....when we only had four or five channels on the control head, deputies would carry scanners so they could a least hear the dispatcher. We had no handheld radios. It wasn't unusual for SRC to send a unit to a location to check on the status of a deputy. Some of the cars (very few) had an "extender" type system much like CHP. The first real handhelds came along in the 80s. It was called the "470" system because they were 470 mHz. These handhelds were used by detectives and special units. I do not believe they were monitored by SRC, however, each station desk had a 470 base station. The 470 frequencies were re-assigned to be data channels for the new/current 480 system. I don't know if this was mentioned, but if you want to use the radio and there is currently no radio traffic being heard, you key the mic and listen. When you key the mic, the system finds (I think they call it voting) an idle dispatch console to receive your message. If all are busy when you key your mic you will hear other stations radio traffic. If you were to key the mic and just talk, you run the risk of stepping over other units. Sorry for the ramble....aaaahhh memories.
Tom
Tom
As I recall, and an old CPRA list confirms, they used 154.80 for those extenders. The CPRA list says "(HT/MO3-Sheriff-east) (to be released for Channel 16) (KA 4308)"
After LASD got moved up to UHF, the City of L.A. got 154.80 for some reason, but I never heard of them ever doing anything with it other than putting it on a list as "LAPD Freq 31." They gave it up in 2006, by which time the late, unlamented Maywood PD had already picked it up and dusted it off. Poor orphan frequency... I wonder where it will go next. "Compton" PD?
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Patriot58
Member
If you still don't like the beep, you can always buy a notch filter...
Yes. When I did my ride-a-long with the deputy, LASO was still on the 39 MHz system and had big whip antennas on their squad cars.
Dave
KA6TJF
Starman918
Member
It was big. On several occasions we would go through parking garages forgetting to clip down the antenna. We would quickly be reminded when we began breaking fluorescent light tubes with the end of the antenna.
ChrisW6YBW
Member
Clarifications to some previously (reasonably good) explanations of the LASD system:
- During emergencies, the PRD is NOT relieved by a supervisor.
- PRD's are NOT "assigned" a group of channels on a daily basis, nor are they assigned a specific channel for continuity.
- Channels are held by the PRD until all calls (or other events) on the channel are code 4. Channels may be passed off from one PRD to another as desired/needed, just so long as someone is holding the channel until everything is code 4.
- Not round-robining call to call. Actually, channels are passed around from PRD to PRD continually.
The LASD radio system (and the way it is implemented) is unique to only one agency in the U.S. It may be awkward (and annoying to listen to for the scanner enthusiasts - believe me, I can relate, listening to the busy tone sucks), but it does have its advantages.
RadioDaze
Member
An audio notch filter could be tuned to mute the tone itself, although it won't release the channel for a return to scan.
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