CHP on my 396xt: Extenders? Centers? Divisions?

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amoking

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All,

Programming for California Highway Patrol is still a bit elusive to me with all of the different bands/mobiles/etc. I am driving from the Bay Area to the Desert (580-5-210-10) in the coming weeks and want to monitor while I drive. I understand the geographic CHP Divisions well enough and can switch over as needed but my questions are these:

Do I need to monitor only the base & mobile vhf frequencies or is it necessary to also monitor the extenders?

Should I monitor the 'Division Wide' or just the traffic coming from the 'Dispatch Centers'?

I am most interested in car to car and local/live incident response.
 

ko6jw_2

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I would concentrate on the dispatch centers. I rarely hear any traffic on division wide frequencies. If you want to hear the cars (within range), you need to monitor both the base and mobile channels. There are some repeaters, but mainly in metro areas. Car to car traffic takes place on the base frequencies. Monitoring extenders is really not necessary as the new 700Mz frequencies are short range. When the CHP used 154Mhz engenders we always monitored them because it was a tip off that a car was nearby. Better than a radar detector! I always program PL decode to be sure I'm hearing the intended base station. The CHP does not simulcast so there may be times when you won't hear the base well and other times when it will be full quieting.
 

scottyhetzel

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When traveling on the 10 east,, when you cross the county line road from San Bernardino to riverside co. You will be in San Gorgonio area.... They handle the area to the whitewater road, just before the dip into the coachella valley...Indio takes it from there to desert center , rice road hwy 177, , Blythe units take it from their to the state line. The Chp use lidar radar. If you see them sideways...this is their method. You need a K40 diffuser to run as cloaking. Chp indio, is at the 10 fwy and Jefferson on the north side of the freeway. I hear Union Pacific police on the chp uhf channel, in San Bernardino you will hear it more often...way more people there.

There is also a thread I started along time ago that the members helped me fill in the blanks...from 10fwy in Santa Monica ocean to the east to the state line on the 10.
 

w9xxx

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The base low bands and the uhf freqs. that's probably 90% of what you'll hear. Use tone squelch (PL tones) if you have the ability. If you program the mobile freqs don't put a delay on them. I've usually figured out where they are at before I'm in range of the extenders. "Close Call" usually only picks up the extenders when you are right on top of them.
 

Tweekerbob

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The division wide channels are typically the Blue channels and are used mainly for aircraft operations. May not be a bad idea to put them in, but the majority of traffic will be on the "other" colored channels for the areas you're travelling through. All low band. As one said, you are almost lucky nowadays to hear a 700 MHz extender. Plug in both the base and mobile freqs to hear the car units. Some areas repeat the mobile units through the mountaintop remote bases, and some don't If you really want to hear the units, get yourself a good external antenna. Otherwise you won't hear them unless they're pulling you over.
 

ko6jw_2

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CHP Division and LA Area Maps

Here are two maps. One shows the CHP divisions statewide. The other shows detail for the Los Angeles area.
 

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amoking

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Thanks everyone.

Are the 154 extenders all gone? I want to say that I heard that 700s replaced them fully.

Any recommendations for a good tuned mag mount antenna? I have plenty of antennas for apco p25 but none for effective & dedicated CHP monitoring.
 

ko6jw_2

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I use the Austin Spectra. It is one of the few mobile antennas that specifically covers the 30-50Mhz band. It comes with a cutting chart for the top whip to optimize it for specific frequencies. I tuned mine with an antenna analyzer, but the chart is very close. It has an NMO mount - so you could get a mag mount or any other kind of mount. Its the best low band scanner antenna I've had in a long time. Also, it can transmit of 2 meters and 70 centimeters and I use it as a backup ham antenna. We don't have much 800Mz use here, but it does well with the California State Parks at 855Mz. By the way, antennas receive RF, they don't care about modulation. Analog and digital are the same to an antenna.

With regard to 154.905 extenders. I think they are mostly, but not entirely gone. I would expect them to be in use in rural areas. Here in the Coastal Division they are not in use anymore. I scan the 700Mz frequencies and I hear P25 extenders if they are close.

Check out the RR Wiki under CHP. There's another map and some other good info.
 

gmclam

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CHP

I just did a drive the other direction (I5, US 20, 101, 199) to Oregon and back and heavily monitor CHP. First and foremost is you need an external antenna good for at least VHF low band. I always monitor the "BLUE" channel for any division I am monitoring. I like to monitor for my present location and an hour ahead of me.

I program in both BASE and MOBILE frequencies with their CTs. I hear as much traffic on the mobile freqs as I do on base freqs in busy areas and times. Keep in mind any dispatcher can turn off the 'repeat' function at any time. Also be aware that "main traffic" can move to BLUE (or visa versa) when there is a (major) incident.

I have also gotten into the habit of using a second (digital) scanner to monitor 700 MHz extender frequencies. When I hear traffic there, I know it is close. I also still monitor 154.905 but it rarely gets hits now. In this scanner I also include things like CLEMARS, CALCORD and CAL TRANS frequencies. You never know where you're going to hear something significant.
 

amoking

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I have also gotten into the habit of using a second (digital) scanner to monitor 700 MHz extender frequencies. When I hear traffic there, I know it is close. I also still monitor 154.905 but it rarely gets hits now. In this scanner I also include things like CLEMARS, CALCORD and CAL TRANS frequencies. You never know where you're going to hear something significant.

Could I not run the 700s at the same time since my 396 is digital? Are you getting hits on the 700s? Which antenna do you use?
 

gmclam

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CHP

What I am doing is running 700 on a digital scanner using a UHF antenna. I separately run a VHF antenna to an analog scanner (PSR-310). First, the GRE digital scanners do a horrible job decoding CT with the DSP on noisy channels (all of low band is fairly noisy) and so I've off-loaded those from the digital scanner. Secondly by using separate scanners I am also using antennas suitable for each band.

Certainly you can do it all with one digital scanner and multi-band antenna. The way I am doing it I only get hits on the digital scanner when someone is close or there is something non-typical going on.
 

amoking

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I thought that was your approach. Do you get much off of the 700mhz channels? Do you know the difference between the Repeater system (obvious) and the Extenders? All are running in the same 769 frq.
 

gmclam

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CHP

I thought that was your approach. Do you get much off of the 700mhz channels? Do you know the difference between the Repeater system (obvious) and the Extenders? All are running in the same 769 frq.
They did what they were intended to do; alert me when near an office or vehicle. I have NACs programmed so I know the difference (as well as LED indication).

Radio traffic for CHP is so varied, likely why I like monitoring so much. At one moment I am hearing dispatcher and repeated car. The next I am hearing car to car (base freq) and the next moment picking up a car replying to dispatch (mobile freq). Very interesting when I pick up a car on both scanners (one on base or mobile freq, the other on extender).
 

amoking

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Gmclam...any thought on a magna-mount tribander (like a Larsen 150/450/800) vs a single 49" 40-50mhz whip (like a Laird C40). You seem to have a lot of hands on knowledge.

HRO says tri-band, Antenna Farm says whip etc etc etc
 

gmclam

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Gmclam...any thought on a magna-mount tribander (like a Larsen 150/450/800) vs a single 49" 40-50mhz whip (like a Laird C40). You seem to have a lot of hands on knowledge.

HRO says tri-band, Antenna Farm says whip etc etc etc
I like mag mounts because I can remove them when I need to. I have a couple of them. One claims 25-1000MHz and the other is a tri-band (not sure of model). I like the loaded models over the whips for many reasons (unless using it to transmit). Go with HRO.
 

amoking

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Either one would be a magna mount. Antenna Farm says that a 150/450/800 won't pull low band well enough.

In your experience do you get much traffic on the repeater freqs...700 and 154 or is it primarily low band 42 mhz? I remember you saying you used 2 scanners.

I'm just interested in picking up as much traffic as I can but not trying to dodge speed traps per se.
 

gmclam

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Either one would be a magna mount. Antenna Farm says that a 150/450/800 won't pull low band well enough.
I get great low band reception on the mag mounts I have. There was a company going out of business a few years back (owner is on RR here) and I bought it there. I have another model that I got from RS last century (and works great too).

In your experience do you get much traffic on the repeater freqs...700 and 154 or is it primarily low band 42 mhz? I remember you saying you used 2 scanners.
154.905 rarely gets hits these days. 700 freqs get hits when I am near a car or office. Low band is where all the traffic is. Because I actually scan the mobile freqs (most don't), and have antennas that receive low band, I get lots of reception there.

I'm just interested in picking up as much traffic as I can but not trying to dodge speed traps per se.
Same here. My interest is in knowing "what is up ahead" whether it is road work, a wreck or something else.
 

jvdet

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Who makes low band radios for them ?? seems the rest of the country is leaving Low band
but low band audio sounds great , wish more users could make some use out of the band
cant wait for the band to open to the west coast....
sorry if off topic
 
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