Inyo National Forest Radio Frequencies.

[SCPD]

Thanks, do you happen to know anything about the Wiki/Database "discrepancy" regarding the Modoc NF Admin Net Frequency. As far as I know, the info in the database reflects the old Admin Net. Do we know if the Wiki info is the new Modoc Admin Net? Thanks,
Bill

The Wiki channel plan for the Modoc is correct. The database is not current and I take the fall for that. After I wrote the Wiki pages I did not make any database submissions based on what I wrote. I believe the Modoc changed the admin net during the late fall, winter, early spring of 2014-2015 or was it the winter prior? I'm working from a hospital bed and don't have easy access to the material that would allow me to pin down when the admin net frequencies were changed.

I'm going to give the Wiki page on last proof read and then request that the person who so kindly took my updates of it to update the database to make sure the database jives with the Wiki.

 

[silverspy]

Thanks. I greatly appreciate your attention to detail, devotion to the hobby and a willingness to teach others like me, who want to learn more, but have far less experience. I started in this hobby in the early 80's and feel like I have gained a greater understanding of the whole, but know that I have a long ways to go. I credit an uncle, who recently passed away, and was in the Signal Corps in Vietnam and later Germany, for getting me started in my interest in and fascination with radios and other communication devices. It has been an honor corresponding with you on this site for the decade or so since I first made a contact, when I was still in Reno. Take care and I hope you feel better soon. I have always considered you one of my mentors in the hobby; one of the relative few who I feel have contributed to my understanding of the hobby and of communications systems in general,
Bill

 

[silverspy]

Just wanted to relay some information that I came across, don't know if it is planned or already in effect. The info has to do with an expansion of the Inyo NF radio system. Here are the new sites, active or proposed, not sure which, and I don't know the corresponding tones.

North Net:
Tioga
Mt.Olsen (NW of Mt.Warren,near Lundy Lake)
Duck Lake(SW of Mammoth Lakes)
Mt.Morgan(SW of Sherwin Summit)

South Net:
Kern
Mt.Whitney
Betty Jumbo(East of Independence)
Palisade
Coyote Ridge
One additional site:Grouse Mtn(SW of Bishop) not sure if this would fall under North or South Net.

 

[SCPD]

Just wanted to relay some information that I came across, don't know if it is planned or already in effect. The info has to do with an expansion of the Inyo NF radio system. Here are the new sites, active or proposed, not sure which, and I don't know the corresponding tones.

North Net:
Tioga
Mt.Olsen (NW of Mt.Warren,near Lundy Lake)
Duck Lake(SW of Mammoth Lakes)
Mt.Morgan(SW of Sherwin Summit)

South Net:
Kern
Mt.Whitney
Betty Jumbo(East of Independence)
Palisade
Coyote Ridge
One additional site:Grouse Mtn(SW of Bishop) not sure if this would fall under North or South Net.

I don't recall what all the sites were, but in an Environmental Assessment written for electronic site reconstruction and upgrading back in the early 2000's a number of new sites were suggested. One new concept was to have some sites in high visitor use areas where SAR's are common was to have a sort of backcountry call box system. The final, approved EA did not include approval for new site construction. The primary remote base for the forest, located on Silver Peak, was to be moved to a nearby peak and I don't think that ever happened and the call box system was not put in place.

What is your source of this information? If you managed to get your hands on this EA, don't rely on it as a source of new sites. The Inyo has some large blind areas on the forest. One is the area south of Mammoth Mountain on the west side of McGee Pass, the entire Fish Creek, Cascade Valley area (Sierra NF area administered by the Inyo), most of the Rock Creek drainage above Toms Place, portions of the Lee Vining Creek drainage near Tioga Pass and around Saddleback Lake, some small areas in the Inyo Mtns and others I've forgotten. Some of the sites you listed may address those blind spots, but at least one would not do much good. The Fish Creek/Cascade Valley/west McGee Pass area would not be covered by a repeater near Duck Lake. We used to put in a temporary repeater extender on Pumice Butte, south of Mammoth Mountain, when we had trail crews working in those areas and when the agency could afford a Cascade Valley Wilderness Ranger. A repeater at Duck Pass, or a repeater extender, would not cover enough country to justify it, however, it would be a location where an emergency call box would work.

I don't have that EA in front of me, it is upstairs where I'm presently unable to go, given not being able to put any weight on my right leg. I will try to remember to get my wife to bring down the right notebook with the EA in it and see if those names match up with the ones you've given me here.

 

[silverspy]

My source for the info is as follows: I came across a site recently on the Internet called Forest Service Repeater Program. It seems to be a program that monitors the "status" of repeaters on different National Forests. It does not look like there are very many sites "online" and being monitored at the time, but when I removed the filter and made the map show all repeaters, even ones not being monitored, I clicked on an inactive circle on the Inyo and a drop down menu showed up, on the right hand side of the screen, listing the sights that I posted. It looks like the data was updated October of this year.
Bill

 

[silverspy]

I also forgot to mention. I'm a little confused about the "Coyote" site. When I visited the old Inyo Dispatch at the airport in the late Nineties, someone gave me the then system map, which showed a "Coyote" sight using 136.5. I always thought that "Coyote" was Keynot Peak, since the 136.5 tone always used to come in very strong and clear in that area. Yesterday, when I checked the Lat/Long on the "Coyote" site that came up more recently, it showed the location as Coyote Ridge,NW of Big Pine. I forgot to mention this in my prior post.
Bill

 

[nd5y]

My source for the info is as follows: I came across a site recently on the Internet called Forest Service Repeater Program.

Interesting but it doesn't appear to have frequencies.
US Forest Service Radio Repeater Program

 

[ecps92]

Yes a very nice site, they have only just really begun adding the West Coast (CA etc) Sites

Interesting but it doesn't appear to have frequencies.
US Forest Service Radio Repeater Program

 

[ecps92]

You need to go over to the right hand side and click on Repeaters
then click on ALL Repeaters

My source for the info is as follows: I came across a site recently on the Internet called Forest Service Repeater Program. It seems to be a program that monitors the "status" of repeaters on different National Forests. It does not look like there are very many sites "online" and being monitored at the time, but when I removed the filter and made the map show all repeaters, even ones not being monitored, I clicked on an inactive circle on the Inyo and a drop down menu showed up, on the right hand side of the screen, listing the sights that I posted. It looks like the data was updated October of this year.
Bill

 

[SCPD]

I also forgot to mention. I'm a little confused about the "Coyote" site. When I visited the old Inyo Dispatch at the airport in the late Nineties, someone gave me the then system map, which showed a "Coyote" sight using 136.5. I always thought that "Coyote" was Keynot Peak, since the 136.5 tone always used to come in very strong and clear in that area. Yesterday, when I checked the Lat/Long on the "Coyote" site that came up more recently, it showed the location as Coyote Ridge,NW of Big Pine. I forgot to mention this in my prior post.
Bill

Keynot Peak and Coyote used to be the locations for the Tone 4 repeater. I think it was on Keynot when I first moved to the eastern Sierra and then got moved to Coyote. Eventually it ended up on Mazourka Peak. The radio tech at the time was trying to get full coverage on the Whitney Trail. Access difficulties led to putting it up on Mazourka. The Inyo already has Mt. Warren, Glass Mtn. and Olancha Peak that can be accessed by helo only and I know maintaining them is difficult. There was already a building on Mazourka Peak for the service net so it wasn't all that hard to move Coyote into it.

I recently received some information from a source on the Inyo National Forest that shows the entire radio repeater system as installed in the computers at dispatch. The repeaters you mention are not on the system. The website you mentioned has it wrong, those sites were proposed in the Environmental Assessment (EA) I have a copy of. As I mentioned the ex radio tech for the Inyo proposed a "call box" type system for emergency notifications in key areas of the John Muir Wilderness where the greatest number of search and rescues occur. The concept was never approved. The EA was available on request for members of the public and I don't recall what type of document contained the negative decision on this call box system.

Another error the website has is that even more call box locations were proposed. One other I can remember was to be located at Kearsarge Pass. Installation of new permanent radio repeater sites is not allowed under the Wilderness Act of 1964, especially a new concept of putting in public call boxes.

 

[silverspy]

Thanks for clarifying. I didn't think it sounded correct for a new repeater site to be on the top of Mt. Whitney. Now with your info, the proposed "call box" deal makes more sense. On a short side note, I remember when I was on the top of Mt. Whitney in August of 1998; back when I still had service with High Sierra Mobilephone and I was using my Bendix King off of Mazourka,I believe. I made a call to a friend to let them know I had reached the summit. Folks were looking at me like I was a little out of the norm. But, boy was that a great Mobilephone Service. Back then they still had their Barcroft site and what an incredible range. Anyway, sorry for the "crosstalk" in the thread, but the idea of the Whitney trail jolted my memory. Take care,
Bill

 

[SCPD]

My wife was able to find the notebook that contained the Environmental Assessment (EA) , dated November 2003, for the "Forest Radio Network System Upgrade." I don't know if this is the final EA or not. There was an earlier version that I read and did not keep or I read online. The earlier version proposed the "call box" function. The 11/2003 version did not propose this function, however, it proposed the permanent installation of "repeater extenders." The Inyo had 2-3 of these while I was working on the forest. One provided coverage for upper Rock Creek Canyon (near the top of the Sherwin Grade) using the Glass Mountain repeater site. Another was brought into the backcountry on foot south of Duck Lake on Pumice Butte on a seasonal basis based on need (trail maintenance projects and the like). These extenders consisted of two military surplus ammunition boxes with surplus Motorola handhelds. one that received the extender frequency and linked that signal to the second box. That box had the second handheld and it transmitted the input frequency to the repeater the extender was dedicated to. The user's radio had to be set to the tone of the repeater the extended linked to. When we entered an unused tone we could use the extender frequency as a backcountry tactical.

The EA proposed to upgrade the extenders hardware. A small trench filled with medium sized rocks was to be used to anchor a antenna pole that was also to be anchored to a small radio vault that was to sit on the ground. The extenders would use new radios and not surplus. The extenders were also going to have the capability of being repeaters using its own frequencies. The forest's hub remote base at Silver was going to be abandoned and a new site constructed at a location one mile north, which was to be named "McKee Peak," in honor of a recently deceased and much beloved forest hydrologist, who died in her late 30's or early 40's.

Most of the new sites were to be extenders and not forest net repeaters. The sites proposed were:

--Lundy Lake, one a ridge just west of Copper Mtn. The website accessed by the link ecps92 provided incorrectly named this one as "Mt. Olsen," which is located at the upper end of Lundy Canyon.
--Tioga Lake, located on a ridge to the north of the lake.
Both of the above would be extenders for Mt. Warren, Tone 1.
--Fish Creek, located on a ridge near Lake Virginia. This is a different location than the traditional placement on Pumice Butte. It probably covers upper Fish Creek better than that provided at Pumice Butte and coverage into the deep upper canyon south of Lake Virginia, called "Tulleys Hole" would likely result. This would be dedicated to extend the coverage of Mammoth Mountain, Tone 2.
--A new repeater would be located on White Mtn. Peak, a mountain that is just 232 feet lower in elevation than Mt. Whitney. I've spent time on this peak and received Mt. Charleston on the Humboldt-Toiyabe NF system.
--Rock Creek, located on a ridge to the east of the canyon. This is an extender dedicated to bringing coverage of the Glass Mountain, Tone 3 repeater into a heavily visited canyon where electronic communications don't reach. This installation would have replaced an existing "ammo can" extender.
--Bishop Creek, located on a ridge above the Aspendell area near Lake Sabrina. I believe this extender was to be dedicated to the South Forest Net, Silver Peak repeater, Tone 8.
--Kearsarge Peak, located on a ridge about 1.5 miles east of the Sierra Crest and Kearsarge Peak and most likely tied into Mazourka Peak, Tone 4.
--Mt Whitney Trail, located on a ridge south of Lower Pine Lake. I think this would be linked to Cerro Gordo Peak, Tone 5.
--Three Rocks, located on the Kern Plateau about 6-8 miles north of Olancha Peak and tied into the repeater there, Tone 6.

I believe that Silver Peak would no longer have a repeater located at the remote base facility. It would be replaced by the White Mtn. repeater. There is a research building on top of the peak that would have provided a well protected location for the repeater and a good anchor for an antenna. A repeater at this elevation, only 280 feet lower than Mt. Whitney, would have a very high potential for interference across most of Nevada and even west of the Sierra Nevada crest.

If you compare the locations given on the repeater website you looked at, you will see that some of the locations given match this list of proposed new and permanent extenders. Others I've never heard of. I'm not aware of any of these extender sites being developed. I'm not sure that the extender at Rock Creek is still in place. I don't know how that canyon is covered now. On one of my trips up there a year ago I used my "repeater stimulator" to see if the Glass or Silver repeaters would work and they did not.

I see no mention in the EA about a site on Coyote Ridge, which is not the "Coyote" Peak, Mountain where the Tone 4 repeater once existed. This Coyote Ridge, according to the website is located west of the Coyote Plateau area just southwest of Bishop. It might be a incorrect description of the proposed extender site designated "Bishop Creek" in the EA.

Most of the site shows repeater locations in the "unhealthy repeater" classification so the data should be considered as dubious at best. The site, in spite of the webmasters attempt to make it look official, is not affiliated with the U.S. Forest Service. I would hazard a guess that the Forest Service logos used on the site is not the result of permission to do so from the agency. I could be wrong, but I'm going to explore the site more. With some hours of work I could locate existing repeaters better than this website has. I have quite a bit of knowledge of the topography of California and I've used quite a few of the repeaters on most of the National Forests in the state.

 

[silverspy]

Thanks for the detailed clarification. I also noticed, after looking at the Forest Service map for the Inyo, that the locations on that website all seem to be off in location by about an entire minute. Just to be sure, I looked at some of the other National Forests and found the same thing. I remember you saying awhile ago, something about there being no more official Forest Service radio techs. Is that pretty much the case agency wide now, all contract work? If that's the case (I could be wrong), it would seem like they would not know the Forests or sites as well as someone who has been in the area for a long time,especially if they are traveling around and working on multiple forests and systems.

 

[SCPD]

Thanks for the detailed clarification. I also noticed, after looking at the Forest Service map for the Inyo, that the locations on that website all seem to be off in location by about an entire minute. Just to be sure, I looked at some of the other National Forests and found the same thing. I remember you saying awhile ago, something about there being no more official Forest Service radio techs. Is that pretty much the case agency wide now, all contract work? If that's the case (I could be wrong), it would seem like they would not know the Forests or sites as well as someone who has been in the area for a long time,especially if they are traveling around and working on multiple forests and systems.

The Inyo now has a full time tech. The destruction of this branch of the Forest Service lies in the George W. Bush administration. They had some type of process that reviewed every function in the Forest Service to see if it should be contracted out. I had retired by then. My experience, which consisted of dozens of situations with contractors during my 25 year career, led me to use the phrase "half the job for twice the price" when looking at most contracting efforts. We had dedicated people in both the electronic/radio systems group and the vehicle maintenance group. The Bush administration formula found that both functions were very efficient and productive. The administration was not satisfied as it was dealing from an idealistic perspective, the myth that government employees cannot accomplish work as efficiently as the private sector. A second study was initiated and came to the conclusion that both functions were accomplished more efficiently by government employees. The problem with contracting is you cannot contract out dedication and wanting to be part of a cause much bigger than yourself. Both electronics and vehicle maintenance had many employees who had worked in private industry and wanted to be a part in what a land management agency was created for.

So the administration directed the Forest Service for round three of the evaluations. For both electronics and vehicle maintenance the agency was REQUIRED to give each function a rent free work area or shop; and provide free utilities, phone, computers, etc. Only then did the contractors measure out as "more efficient." What followed has been pretty much disastrous. Radio repeaters locked on transmit for a couple of days, handhelds not repaired after a period of months, incorrect radio programming and contractors asking Forest Service employees how to take handhelds apart. The mechanics did not know how to work on engines, would not come out into the field to make repairs like the Forest Service mechanics did and weren't very good about solving problems on various apparatus. In one case an Angeles engine was rolling Code 3 on the Angeles Crest Highway when an engine, just released from maintenance, lost an outer wheel on the rear axle, which bounced over the side and made the engine very difficult to control it to a stop.

Forest Service mechanics and electronic techs could pull rabbits out of hats. The Inyo NF extenders used materials usually obtained from surplus military supply at San Bruno for antenna steel, coax, the ammo boxes and even small solar panels. The radio tech kept the Motorola MT-500's (crystal radios) and used them for all sorts of things. Those extenders took care of some large and critical holes in coverage and for tens of dollars considering everything was used.

I only have a limited view of what is happening now, but the Inyo was assigned a government employee to maintain the radio system full time. This is not a person in a distant big city like Reno or Sacramento, this person lives and works in Bishop full time.

 

[silverspy]

Question.
Do you by chance know how the Sweetwater site for the Inyo is tied into the Silver Peak remote base "hub"? It does not appear that there is a direct path between Sweetwater and Silver.
2nd Question, and sorry if I'm straying slightly off the topic of the Inyo NF, but this question relates to Forest System radio systems in general. So, if for instance, the remote base simultaneously receives, say, signals from four different repeaters on the net and decodes the tones, is only one signal successfully received at the console, or do the other three go into some sort of queue at the console, indicating to the dispatcher what repeaters the other three signals came from,or if this happens, do the other transmitting units just have to repeat their "covered" traffic?

 

[vlarian]

Question.
Do you by chance know how the Sweetwater site for the Inyo is tied into the Silver Peak remote base "hub"? It does not appear that there is a direct path between Sweetwater and Silver.
2nd Question, and sorry if I'm straying slightly off the topic of the Inyo NF, but this question relates to Forest System radio systems in general. So, if for instance, the remote base simultaneously receives, say, signals from four different repeaters on the net and decodes the tones, is only one signal successfully received at the console, or do the other three go into some sort of queue at the console, indicating to the dispatcher what repeaters the other three signals came from,or if this happens, do the other transmitting units just have to repeat their "covered" traffic?

I can't speak for the Inyo, but I can speak to how it works on the Sierra. On the Sierra if two or more field units transmit on the same channel at the same time, they cover each other. Tones can be the same or different it does not matter, dispatch hears both parties simultaneously. Usually the dispatcher can make out part of the conversation, but will need the units to repeat (hopefully one at a time).

the Sierra dispatch center (AKA "Sierra" or "Sierra ECC") uses a base transceiver located at the Fresno Air Attack Base which is in Fresno, CA. the transceiver is like any other base station, except more powerful and has a really great antenna. Dispatch also has links out in the field. we call them "links", but that is a local term for these electronic sites that the forest uses. each repeater transmits a tone, these tones are decoded at dispatch, this trips a relay that signals the dispatch console which repeater is transmitting. this shows up as a number, i.e. a "5" would appear on the moducom console's screen. the dispatcher is trained to understand that this means shuteye repeater is transmitting. therefore the field unit is using tone 5 and must be within range of that repeater. the dispatcher has to choose manually which tone they wish to TX on, they usually return these calls on the same tone that the caller used. so you see the dispatcher must choose the correct tone for the area that the recipient is located in.

the Sierra dispatch has the ability to transmit remotely from a few sites across the Sierra NF. (interesting note the Sierra does not use tone remote control for this process, they use E&M signalling) however when they do they can not choose a tone. for instance the dispatcher can choose to transmit from the site at white Bark Vista. but they can not choose what tone is transmitted. this serves to cover areas of the forest that the base station located in Fresno can't reach. these "links" also bring audio back to dispatch allowing them to hear the field units. this capability allows the dispatcher to hear units when the signal from that field unit is not reaching the base station in Fresno. all of the monitors (which only return audio to dispatch) and the remote bases on the Sierra receive signals on Simplex 172.2250(Emergency net) and 171.4750 (Admin net) these are the direct, talk around, simplex, or car-to-car channels. this allows the dispatcher to hear conversations that the field units believed to be private since they are not transmitting on a duplex channel or using any tones.

here is the part I am hazy on; how exactly the remote sites and monitors are connected to the dispatch center. this is what I do know. There is a microwave signal that starts at dispatch runs direct to Musick Mt, then to White Bark Vista. Musick Mt is connected to Goat Mtn via a microwave signal and from there it hops down via microwave to the North Fork Ranger Station. there is a UHF connection between the repeater/monitor at Patterson Mt and dispatch. however exactly where the UHF receiver on the other end from Patterson is located, that I do not know.

in case you were wondering and I know this is a bit off topic but hey,

Repeaters:
Signal Pk Tone:2 Admin and Emerg nets
Shuteye Tone:5 Admin and Emerg nets
Mt Tom Tone:7 Admin and Emerg nets
Mt Givens Tone:9 Admin net only
Black Mt Tone:6 Admin and Emerg nets
Fence Meadow Tone:12 Admin and Emerg nets
Deliah Tone:8 Admin and Emerg nets

Repeaters and Remote bases:
Bullion Tone:1 Admin, Emerg and Service nets
Musick Mt* Tone:3 Admin, Emerg and Service nets Also the Remote base for National Flight Following and Air Guard
White Bark Vista* Tone:9 Emerg and Service Nets

Remote bases:
Deadwood Admin net only
Goat Mtn* Emerg net only

Repeaters and Monitors:
Patterson Tone:4 Admin, Emerg and Service net (UHF)

Base stations only:
Sierra Dispatch Center*
Supervisor's Office
Prather (High Sierra Ranger District Office)
North Fork (Bass Lake Ranger District Office
El Portal Station
Jerseydale Station
Minarets Work center
High Sierra (visitor/information center)
Eastwood (visitor/information center)
Dinkey (visitor/information center)
Mariposa (visitor/information center)
Oakhurst (visitor/information center)
Clover Meadow (visitor/information center)
The Fresno Air Attack Base base station radio is connect to and shares the same transceiver that dispatch uses.

*: has a microwave connection

 

[silverspy]

Thanks for the detailed clarification,
Bill

 

[SCPD]

Question.
Do you by chance know how the Sweetwater site for the Inyo is tied into the Silver Peak remote base "hub"? It does not appear that there is a direct path between Sweetwater and Silver.
2nd Question, and sorry if I'm straying slightly off the topic of the Inyo NF, but this question relates to Forest System radio systems in general. So, if for instance, the remote base simultaneously receives, say, signals from four different repeaters on the net and decodes the tones, is only one signal successfully received at the console, or do the other three go into some sort of queue at the console, indicating to the dispatcher what repeaters the other three signals came from,or if this happens, do the other transmitting units just have to repeat their "covered" traffic?

The Sweetwater electronic site gets into Silver full quieting. This, even though the site is really not high as it is located well below the crest of the range. There are places in Reno where I can bring up the 2m ham repeater located at Sweetwater. I easily bring up the Silver 2m repeater on a handheld using 5 watts from the Sweetwater site. There are very few marginal spots in the 800 Mhz coverage on 395 between the state line and Conway Summit from Sweetwater. Silver is also a surprisingly good site even though it is on a relatively small bump on the west side of the White Mountains. Many people will point to White Mtn. Peak and think that is Silver, but they are off by 17 miles and nearly 3,400 feet in elevation. I can bring up the Silver Peak 2m repeater with a 50 watt mobile using a 18" dual band antenna from a spot near Holbrook junction, the first highway junction on U.S. 395 in Nevada north of the California border. There has been considerable investment at both sites. Silver Peak is the hub for most of the radio systems in the eastern Sierra, with the exception of Conway Summit, the hub of all the Mono County radio systems.

Your second question about what happens in dispatch when four repeaters within the range of one remote base are transmitting simultaneously. As far as I know it is no different than when any receiver is within reception range of four repeaters and I call that "repeater wars." The sound consists of squealing and other "gnashing of teeth" type sounds. However, I haven't been in a dispatch center that uses a high elevation remote base linked by 400 MHz in a very long time. There are four different signals being received by the remote base receiver and all four are then retransmitted on one UHF frequency down to dispatch. When one repeater transmits the VHF receiver sends the signal over to a UHF transmitter and in dispatch a UHF receiver analyzes the sub-audible tone (CTCSS) present, reports that to a computer, which in turn causes the box representing the transmitting VHF repeater to change color and/or flash. I don't think the tone is decoded until it reaches the downlink receiver at dispatch. I don't think that radio has the capability of excluding all tones except for one, but I could be wrong here. When the dispatcher is working one repeater by touching the box representing it on the screen signals it is essential that other repeaters be heard, in case of more urgent traffic. I'm not sure if the dispatcher has the option to turn down or mute the volume of the non selected repeaters. I know they can when several nets are controlled from the same console enabling them to lower the volume or mute each net of all the nets except one, two, or whatever is desired. For example, if the dispatcher is working an aircraft down incident on forest net, they can turn down the law enforcement, service, and admin nets as well as the microwave ops dispatcher intercom. If they can pull that one repeater out of the mess and mute the other three it still leaves the issue of four simultaneous signals coming down from the remote base on one UHF frequency. In order to select only one tone to be sent down the downlink frequency would mean that the dispatcher's console would have the capability to change or control the receive tone of the VHF receiver of the remote base. That would be the best case, however, four simultaneous signals will still cause some interference. The signals of each might only have a very slight difference based on distance, path and electric supply factors as localized weather may affect battery strength at repeater sites that have experienced a lot of cloudiness when others have not and some may have commercial power as well.

Any dispatcher has to assert control of a net when multiple units transmit. If a dispatcher is able to discern one of your four hypothetical repeaters should allow the air to clear and then state: "we have multiple units transmitting any unit with emergency traffic go ahead." PAUSE. "Unit on tone X, go ahead with your traffic, all other units stand by." Following that I would pick another, often used repeater and state: "Unit on Tone Y, go ahead with your traffic, all other units stand by" and then do the same for Tone Z until all units that had been transmitting at once have been able to communicate. It is likely that 1 or 2 of those units are transmitting status changes, one is calling another mobile unit and maybe one has traffic you have to follow up on.

How the competition for the net is handled is based on the triage structure found in the dispatch center operating plan or guide. The order found in those are usually, life and death, aircraft, significant employee or public injury, law enforcement officer high risk situations, new fire reports, on going fires, other law enforcement incidents, weather reports and administrative traffic. Dispatch centers outside of California don't usually mention law enforcement as most have chosen to not provide law enforcement dispatching services.

 

[silverspy]

Thanks.

 

[vlarian]

Interesting how these two forest which share a common border have different radio systems. The Forest Service allows each forest to make what every system that works best for them. unlike CDF which is pretty rigid.

The Inyo and the Sierra both use ModUcom computerized dispatch consoles. this system allows for infinite customizations. for instances the Sierra Dispatcher has the ability to set the volume independently for selected lines, un-selected lines, aviation lines, and monitors. if that was not enough they can control the volume for each channel or line (SNF Admin, Emerg, Service, Air-To-Ground, etc.) independently. they can mute all (but this only last about five seconds) or mute any line (this mute is a toggle, the line will remain muted till the operator release the mute.).

and for giggles; the ModUcom console can be setup into screens, with different functions
Lines on the Sierra screen
TX and RX Capabilities;
Admin net
Emerg or fire net
Service net
CAL Fish and Game (the dispatcher can choose which remote base to transmit and listen from: musick or Bullion)
National Flight Following
Air Guard Jaquin Ridge (this is provided by the state)
Air guard Musick Mtn (this is a FS site)
Law Enforcement Net
North ops Forest Service
South Ops Forest Service
Sierra Intercom
Travel North
Stanislaus Ops net
CESRS

Monitor only:
air-to-ground
SQF Fire net
YNP Fire net
Air Tactics 3
Air Tactics 6
Madera SO
Fresno SO
Merced CHP
Fresno CHP
Crew net
MMU Local
TUU Local
Fresno city Fire channel 2
Clovis City Fire
FKU Local 1
FKU Local 2
Fresno county District 1

Sierra Dispatch shares its radio system with the Fresno kings unit of Cal Fire, that leads to some of the monitor channels being for them.

in case you were wondering what the FKU screen of the ModUcom looks like:
CDF Command 1
CDF Command 2
CDF Command 4
OES Fire 1
OES Fire 2
CERSRS
Air Guard Joaquin Ridge
Air Guard Musick
FKU Local 1
FKU Local 2
Sierra Intercom (Intercom with the Sierra region CDF units and forests)
City Intercom (Intercom with Fresno city fire)
Vfire 21
Fresno County Fire district 1
Fresno County Fire district 2

one last off topic tid-bit
all CDF ECCs, all contract counties, both the Northern Operations Center (NOPS) and the Southern Operations Center(SOPS), most Air tanker bases, most Forest Service forests and a few Nation Park Service parks are connected to the "intercom". This microwave radio network spans the whole state. But it is broken out into the channels North, Sierra and South. All units in NOPS are on the "North intercom" all units between the NOPS/SOPS border and north of LA, Santa Barbara, Ventura, and west of San Bernardino, Inyo and Mono counties are on the "Sierra Intercom". Inyo, mono, San Bernardino, LA, Ventura, Santa Barbara counties and all places south are on the "South Intercom". On the Sierra Intercom Yosemite is the only NP. Oddly Kings Canyon/Sequoia NP is not on the intercom.

I think me and Exsmokey were cut from the same cloth, when it comes to the gift of gab.