CalTrans Maps...

franks_ham

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I know there is the generic "District" map, but does anyone have or know of a "Tower" map...I'm looking particularly for District 2 and 3 maps. I get the "general idea" of where some of the places are based on the scanner descriptions but I'd like to "lock-in" on each repeater as I travel.

Regards,

-Frank C.
 

es93546

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I know there is the generic "District" map, but does anyone have or know of a "Tower" map...I'm looking particularly for District 2 and 3 maps. I get the "general idea" of where some of the places are based on the scanner descriptions but I'd like to "lock-in" on each repeater as I travel.

Regards,

-Frank C.
It is hard to find maps on the Caltrans site. I came into possession of a document showing statewide and district communications sites courtesy of Robert Kelty many years ago (32+). It is now very much out of date. It was the statewide plan of how Caltrans was going to switch to 800 MHz from VHF-Low. It came right from the pages of a book maintained by what is now the OES communications agency. He gave me copies of other state systems from that book, but I have no idea of how he was able to. These days this information might be more closely protected.

I appreciate what you said about locking into various repeater sites as you travel. The information gained can be very useful while driving. I do the same thing. I actually have various "files" (for my GRE PSR 500/600's) for various areas of the state. I have groups programmed for CHP and Caltrans, one each for my metro area files and combined for the rural areas. Doing that lessens the need to lock on each repeater. After all, we don't have local information about what repeater covers a given area.
 
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franks_ham

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It is hard to find maps on the Caltrans site. I came into possession of a document showing statewide and district communications sites courtesy of Robert Kelty many years ago (32+). It is now very much out of date. It was the statewide plan of how Caltrans was going to switch to 800 MHz from VHF-Low. It came right from the pages of a book maintained by what is now the OES communications agency. He gave me copies of other state systems from that book, but I have no idea of how he was able to. These days this information might be more closely protected.

I appreciate what you said about locking into various repeater sites as you travel. The information gained can be very useful while driving. I do the same thing. I actually have various "files" (for my GRE PSR 500/600's) for various areas of the state. I have groups programmed for CHP and Caltrans, one each for my metro area files and combined for the rural areas. Doing that lessens the need to lock on each repeater. After all, we don't have local information about what repeater covers a given area.
Robert had some good stuff! If you want/wish to share the older docs privately my PM's are open. I try and figure this out on my own but...

I know I'm pretty well "SET" on where CHP is, I have special stuff setup in my TK690 for them. Caltrans is definitely a different beast! Multiple sites for the "same area". It seems like there is a huge gap between Quincy, Pulga and Oroville as to which towers to listen to.

Regards,

-Frank C.
 

inigo88

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This presentation is from back in 2011, but it does an excellent job of explaining how technically complex it was to implement 800 MHz conventional repeaters in districts 1 and 2 given the complex terrain:


To make a long story short, they needed so many 800 MHz repeaters to replace low band that they had to implement vote-scan on the mobile radio receive end just to make it work. If I’m understanding it right, basically each “channel” is actually a series of channels in a scan list in the users mobile radio, all with a common Tx frequency. All the repeaters within the coverage area of that vote-scan channel listen to that common input frequency but then broadcast on their own individual repeater output frequencies. The mobile radio then scans through all those repeater output frequencies, “votes” (picks the strongest one) and then listens to that output frequency. This allows the mobile to roam around between a coverage area of different repeaters on different output frequencies without needing to change channels on the radio.

I often wondered how CALTRANS employees were expected to be such experts on local geography that they could constantly change channels to the closest mountain top every few minutes of driving, and it turns out this is how.

Since the drivers don’t have to change channels very often, the only maps that would exist for what you’re asking would be internal engineering documents for state radio techs, so your best bet is to figure it out through trial and error and determine which groups of repeaters constitute which “vote-scan channel.”
 

es93546

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This presentation is from back in 2011, but it does an excellent job of explaining how technically complex it was to implement 800 MHz conventional repeaters in districts 1 and 2 given the complex terrain:


To make a long story short, they needed so many 800 MHz repeaters to replace low band that they had to implement vote-scan on the mobile radio receive end just to make it work. If I’m understanding it right, basically each “channel” is actually a series of channels in a scan list in the users mobile radio, all with a common Tx frequency. All the repeaters within the coverage area of that vote-scan channel listen to that common input frequency but then broadcast on their own individual repeater output frequencies. The mobile radio then scans through all those repeater output frequencies, “votes” (picks the strongest one) and then listens to that output frequency. This allows the mobile to roam around between a coverage area of different repeaters on different output frequencies without needing to change channels on the radio.

I often wondered how CALTRANS employees were expected to be such experts on local geography that they could constantly change channels to the closest mountain top every few minutes of driving, and it turns out this is how.

Since the drivers don’t have to change channels very often, the only maps that would exist for what you’re asking would be internal engineering documents for state radio techs, so your best bet is to figure it out through trial and error and determine which groups of repeaters constitute which “vote-scan channel.”
I should add that Caltrans is now installing "roadside repeaters" and literally what they are. They are installing repeaters in small utility lockers in the road right of way, just past the shoulder. I've seen several new licenses for these along CA SR 88. I don't know if they know how many of these are going to be needed for what is likely the most problematic location in the entire state for 800 MHz. It is the stretch of U.S. 199 south from the Oregon state line, along the Smith River, to U.S. 101. This is a 37 mile stretch and I heard rumors that it was going to take one of these roadside repeaters at nearly every curve in the road. A bunch of curves with thick trees that have needles just the right length to attenuate 800 MHz signals, which is sort of the double whammy for short wavelength radio.

Now, I'm going to read the document you linked to.
 

es93546

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This presentation is from back in 2011, but it does an excellent job of explaining how technically complex it was to implement 800 MHz conventional repeaters in districts 1 and 2 given the complex terrain:


To make a long story short, they needed so many 800 MHz repeaters to replace low band that they had to implement vote-scan on the mobile radio receive end just to make it work. If I’m understanding it right, basically each “channel” is actually a series of channels in a scan list in the users mobile radio, all with a common Tx frequency. All the repeaters within the coverage area of that vote-scan channel listen to that common input frequency but then broadcast on their own individual repeater output frequencies. The mobile radio then scans through all those repeater output frequencies, “votes” (picks the strongest one) and then listens to that output frequency. This allows the mobile to roam around between a coverage area of different repeaters on different output frequencies without needing to change channels on the radio.

I often wondered how CALTRANS employees were expected to be such experts on local geography that they could constantly change channels to the closest mountain top every few minutes of driving, and it turns out this is how.

Since the drivers don’t have to change channels very often, the only maps that would exist for what you’re asking would be internal engineering documents for state radio techs, so your best bet is to figure it out through trial and error and determine which groups of repeaters constitute which “vote-scan channel.”
Thanks for the great information, both the link and how you explained how these roadside repeaters work. I think I read this document one other time, but an additional read and your explanation was needed to fully understand it well enough to program a scanner. I think trying to lock in tones would be counterproductive as there might be many repeaters on the same highway segment with the same output frequency. Counterproductive in that it would take several channels to cover each tone, using memory and slowing the scanner down.

Here in the eastern Sierra there are some problematic areas of coverage for 800 MHz. I'm real familiar with the Mono County and northern Inyo County areas that have lousy coverage. SR 158, the June Lake Loop and SR 120 west of U.S. 395 have never had 800 MHz coverage, since the 1982 conversion of CT D9. This is especially dangerous on SR 120 as we are talking about Tioga Pass, the eastern entrance to Yosemite. The June Lake Loop is also dangerous. There are some avalanche prone areas on it, plus a lot of traffic in the winter due to the June Mountain Ski Area. The northern portion of the loop is closed for much of the winter as a CT employee lost his life in an avalanche there. There is one resort and a horse packing business in that stretch, neither operate in the winter, so closing the stretch is not a huge issue. On the south side of June Lake (not the town of the same name) there is a large avalanche zone. A system of propane fueled explosive tubes have been installed, which can be fired remotely, has been installed to trigger avalanches when the road is closed. A county road was completed north of the town, which now provides bypass access during avalanche closures here. Snow removal in the spring on Tioga Pass is quite hazardous and about 5 miles west of 395, there is no coverage for anyone except CHP and the U.S. Forest Service, although iffy in spots.

Caltrans has been issued several 400 Mhz licenses in these two areas, however, I haven't seen any new 800 MHz licenses. They have had a couple of phases of licensing and not all the sites have been kept under license in the 2-3 phases of licensing they have undertaken. So I will continue to watch new licensing in an attempt to figure it out.

In northern Inyo County they have some problems along U.S. 6 due to shadowing from the Silver Peak site in the White Mountains. There are also some spotty areas along SR 168 east of U.S. 395. There are some grades and canyons along this route that need coverage improvement, although the traffic on this road is light and a lower priority. It is a highway section posted with "Snow Not Removed 4 p.m. to 8 a.m." or similar.

It will be interesting to see what CT does in these 3 areas. All are subject to snowfall and all need coverage.

In southern Inyo County I think some peaks and one elevated electronic site are providing coverage, however, my time down there is limited to 10-15, camping trips of 1-4 nights in Death Valley and one 4 night trip to the small towns of Shoshone and Tecopa. If you want more than 1 restaurant to choose from this is no place for you!

I wish we could get our hands on an "as built" list of channels for every district, similar to the one provided in this rural radio coverage presentation these two engineers did.

Thanks!

Regards,

-Frank C.
After reading inigo88's post and the document he provided a link to, I think you need to reconsider locking on to a single frequency while mobile. When I scan Caltrans I have all the CT district's frequencies in one bank, sometimes by itself and sometimes combined with CHP. What we need is a listing of all the 800 MHz frequencies used CT district by district, including all the voting or roadside repeaters. .
 

franks_ham

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After reading inigo88's post and the document he provided a link to, I think you need to reconsider locking on to a single frequency while mobile. When I scan Caltrans I have all the CT district's frequencies in one bank, sometimes by itself and sometimes combined with CHP. What we need is a listing of all the 800 MHz frequencies used CT district by district, including all the voting or roadside repeaters. .
I know RadioReference goes District by District in the 800 CT frequencies...I just find it odd that there seems to be a HUGE gap between Quincy, CA., and Pulga, CA., which is, well VERY mountainous to say the least. On the railroad, we have a hard time on VHF up there with some comms!

I'm headed up that way the end of the week and that's why I asked as I'm re-programming a few banks/zones dedicated to this trip...Each has it's own list and area to cover.

Regards,

-Frank C.
 

norcalscan

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I know RadioReference goes District by District in the 800 CT frequencies...I just find it odd that there seems to be a HUGE gap between Quincy, CA., and Pulga, CA., which is, well VERY mountainous to say the least.
Take a look at KNCM796 for the 800Mhz in Feather River Canyon, and WQUS522 for their UHF links. KMA276 is the lowband 47.100 on Red Mtn covering the entire area. Working further up 70 towards Quincy puts us in Mt. Hough coverage near Keddie Wye, WQBG888 has your 800 there. That'll give you Caltrans all the way up the canyon to Quincy.

The 800 is all there on the RRDB for Caltrans. The Pulga and Quincy channels for District 2.

And while the Google street view is from 2012, sat view has Location 6 for KNCM796 just below Rodgers Flat in the canyon, showing the roadside enclosures and mast of the typical DOT 450/800 remote bases.
 
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franks_ham

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Take a look at KNCM796 for the 800Mhz in Feather River Canyon, and WQUS522 for their UHF links. KMA276 is the lowband 47.100 on Red Mtn covering the entire area. Working further up 70 towards Quincy puts us in Mt. Hough coverage near Keddie Wye, WQBG888 has your 800 there. That'll give you Caltrans all the way up the canyon to Quincy.

The 800 is all there on the RRDB for Caltrans. The Pulga and Quincy channels for District 2.

And while the Google street view is from 2012, sat view has Location 6 for KNCM796 just below Rodgers Flat in the canyon, showing the roadside enclosures and mast of the typical DOT 450/800 remote bases.
Thanks for that! When I think Pulga, I think of PULGA itself not 3 other locations between Oroville and Pulga being on the same frequency! :) So Pulga/Quincy/Beckwourth do cover the canyon from Oroville to Hallelujah Jct well! Thanks.

Regards,

-Frank C.
 

es93546

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Take a look at KNCM796 for the 800Mhz in Feather River Canyon, and WQUS522 for their UHF links. KMA276 is the lowband 47.100 on Red Mtn covering the entire area. Working further up 70 towards Quincy puts us in Mt. Hough coverage near Keddie Wye, WQBG888 has your 800 there. That'll give you Caltrans all the way up the canyon to Quincy.

The 800 is all there on the RRDB for Caltrans. The Pulga and Quincy channels for District 2.

And while the Google street view is from 2012, sat view has Location 6 for KNCM796 just below Rodgers Flat in the canyon, showing the roadside enclosures and mast of the typical DOT 450/800 remote bases.
Great research! You do research the same way I do. I try to do my FCC license research after 2 p.m. Pacific time because the east coast is at 5 p.m. and the FCC site is quicker. I have Google Earth booted up nearly all the time. I do quite a few lat/long searches on it. Thankfully it accepts all the different lat/long formats so I can copy and paste it into the search box. The FCC has symbols that have to be deleted however. A "-" has to be inserted in front of the longitude or you end up in India, because the dash indicates the western hemisphere. With all that effort it is amazing what you can figure out. I've looked at the street view of many federal natural resource agency dispatch centers looking to see if the antenna tower has 400 MHz beam antennas or microwave dishes. That can help to figure out what type of linking system might be used. If the electronic site is located at a lookout tower, often times someone has posted a picture of the lookout and viewing the antenna towers on them will help as well.

Back to Caltrans, the database abbreviation monster has struck again. On the statewide frequency table there are many lines where "MPL" is shown. I think that might have something to do with the roadside repeaters, however, I don't want to make assumptions. It should have been explained in the description, but the database is so full of unexplained abbreviations TIMAWSC "Tim a Wa Sic" (That I Might As Well Stop Complaining). If I find out what it means I will make a submission to the database as part of my NEMTC "Nem Tic" (Never Ending Mission to Clarify).
 
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norcalscan

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Back to Caltrans, the database abbreviation monster has struck again. On the statewide frequency table there are many lines where "MPL" is shown.
MPL is Multi or Multiple PL, sort of the standard term in radio programming and end-user radio interfaces that designates this channel has multiple tone options so change tones to change repeaters, vs change channels to change repeaters. For instance, Moto uses MPL in their interface, Kenwood (not sure on their NX line) uses OST (operator selectable tone) and KNG's call them Code Guard (CG) Picklists.
 

franks_ham

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MPL is Multi or Multiple PL, sort of the standard term in radio programming and end-user radio interfaces that designates this channel has multiple tone options so change tones to change repeaters, vs change channels to change repeaters. For instance, Moto uses MPL in their interface, Kenwood (not sure on their NX line) uses OST (operator selectable tone) and KNG's call them Code Guard (CG) Picklists.
Kenwood has OST on their NX line, at least the NX2/700 series!

Regards,

-Frank C.
 

franks_ham

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Great research! You do research the same way I do. I try to do my FCC license research after 2 p.m. Pacific time because the east coast is at 5 p.m. and the FCC site is quicker. I have Google Earth booted up nearly all the time. I do quite a few lat/long searches on it. Thankfully it accepts all the different lat/long formats so I can copy and paste it into the search box. The FCC has symbols that have to be deleted however. A "-" has to be inserted in front of the longitude or you end up in India, because the dash indicates the western hemisphere. With all that effort it is amazing what you can figure out. I've looked at the street view of many federal natural resource agency dispatch centers looking to see if the antenna tower has 400 MHz beam antennas or microwave dishes. That can help to figure out what type of linking system might be used. If the electronic site is located at a lookout tower, often times someone has posted a picture of the lookout and viewing the antenna towers on them will help as well.

Back to Caltrans, the database abbreviation monster has struck again. On the statewide frequency table there are many lines where "MPL" is shown. I think that might have something to do with the roadside repeaters, however, I don't want to make assumptions. It should have been explained in the description, but the database is so full of unexplained abbreviations TIMAWSC "Tim a Wa Sic" (That I Might As Well Stop Complaining). If I find out what it means I will make a submission to the database as part of my NEMTC "Nem Tic" (Never Ending Mission to Clarify).
It is fun to cross-reference like that but unless I'm SUPER curious, I try and leave that to the people with "more time" on their hands!! ;)

Regards,

-Frank C.
 

es93546

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MPL is Multi or Multiple PL, sort of the standard term in radio programming and end-user radio interfaces that designates this channel has multiple tone options so change tones to change repeaters, vs change channels to change repeaters. For instance, Moto uses MPL in their interface, Kenwood (not sure on their NX line) uses OST (operator selectable tone) and KNG's call them Code Guard (CG) Picklists.
Thank you! I new about OST because the feds use that for their tone selectable channels. I was a fed once who used my radios a lot as a first responder, ICS aficionado, field supervisor, blah, blah, blah. I knew that BK insisted it be called "Code Guard." On my handheld I only put the squelch knob past the detent to enable the PL filter on the business frequencies I was authorized to use. It was necessary otherwise the frequency of cross country ski center I patrolled was also used at a couple different condo complexes in town for housekeeping. I wasn't interested in hearing that 402 needed 2 rolls of toilet paper and 4 hand towels. We used a few different brands of radios over an entire career, so we just called "a tone" or sometimes "PL." We memorized where repeaters were and which covered certain areas and tied in the tone number to all of that.

So manufacturers can't call something the same thing, they have to have all their own brands have all the different terms of the same things everyone else has. Ah, capitalism really can suck at times, but it works better than nearly everything else we've tried. Kind of like democracy.

I'm going to suggest that MPL, where used be listed in the database, be explained in the description column. There are far too many abbreviations and cutesy little words in the world.
 

es93546

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It is fun to cross-reference like that but unless I'm SUPER curious, I try and leave that to the people with "more time" on their hands!! ;)

Regards,

-Frank C.
I spend some time keeping track of the systems in the eastern Sierra. I want to understand how every system works, down to the small details. I'm also interested in the natural resource/land management agency systems I hear from my home or while I'm mobile, especially the units (park, forest, BLM field office, etc.) I travel to frequently. If a link frequency is used that I can receive it enables hearing a lot more. I can hear 3 national forests, 1 national park LE net and two BLM districts from my home.
 

es93546

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I have another observation of the Caltrans database, in the alpha tag the letter V and a number (one letter as well) are used on at least half the districts. It has nothing to do with the listed frequency V, so this is confusing also. Someone else must understand this. If V stands for something, can't something else be used so we don't confuse it with frequency V? Either that or show a note at the top explaining what the letter V stands for.
 

franks_ham

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So manufacturers can't call something the same thing, they have to have all their own brands have all the different terms of the same things everyone else has. Ah, capitalism really can suck at times, but it works better than nearly everything else we've tried. Kind of like democracy.
I know Mother /\/\ being how they are trademarked PL/MPL a long time ago...Probably why BK went with Code Guard so they couldn't be called out...

On the other topic of keeping track of systems, where I'm at, it's sooo isolated in some ways (Cloverdale) that we have nothing going on but at the same time we have A LOT going on around us! I can listen to so much in a 24 hour period and yet it can be quiet for days on end.

Regards,

-Frank C.
 

franks_ham

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I have another observation of the Caltrans database, in the alpha tag the letter V and a number (one letter as well) are used on at least half the districts. It has nothing to do with the listed frequency V, so this is confusing also. Someone else must understand this. If V stands for something, can't something else be used so we don't confuse it with frequency V? Either that or show a note at the top explaining what the letter V stands for.
I have to second this, I have NO idea what "V" stands for. I have it in my line up though as the alpha-tag just to be safe!

Regards,

-Frank C.
 

norcalscan

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I have another observation of the Caltrans database, in the alpha tag the letter V and a number (one letter as well) are used on at least half the districts.
Logical deduction for me after seeing Inigo's posted presentation, is that is the vote-scan grouping for each of those channels. As far as dispatch and end-users are concerned, they tune to Adin, Alturas, Burney, Chester etc. The dispatcher's transmissions will come across all of those Adin channels, and the end-user's radio is transparently scanning/voting those 3 channels and selecting the clearest one. If the end-user wants to reply, within a determined time-frame I'm sure the PTT will select the last-"best" channel heard to transmit back on. Depending on what that was, the transmission goes to the primary site directly, or hits one of the roadside crossband remote bases and gets back to the primary site that way.

The presentation immediately made me rethink how to scan Caltrans while mobile, and depending on my routing, I don't have to worry about the V's unless I know I'm going deep along the rural routes of 36, 299, etc. I've scanned the UHF links multiple times while deep down 36 and 299 to the coast with no luck, only got 800 transmissions so between the low power and directional antennas, the UHF links are likely not beneficial to mobile users.
 
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