Major brush fire N of Goleta (Scherpa or Sherpa Fire)

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SLOweather

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Santa Barbara County has now declared a Local State Of Emergency.

And the NWS has issued a Special Weather Statement for So cal:

"...POTENTIAL DANGEROUS RECORD BREAKING HEAT ACROSS SOUTHWESTERN
CALIFORNIA SUNDAY THROUGH TUESDAY...

...ELEVATED FIRE DANGER ACROSS SOUTHWEST CALIFORNIA SATURDAY THROUGH
TUESDAY DUE TO COMBINATION OF VERY HOT AND DRY CONDITIONS...WITH
BRIEF CRITICAL FIRE WEATHER CONDITIONS POSSIBLE ACROSS SOUTHERN
SANTA BARBARA COUNTY DUE TO GUSTY SUNDOWNER WINDS..."

More at National Weather Service - NWS Los Angeles/Oxnard.

On the 3rd day now. Many pix and vids at https://www.facebook.com/SLOStringer/ and https://twitter.com/SLOStringer.

101 closed NB and SB last 2 nights from about 8 to 8 due to sundowner winds.

Per inciweb this morning InciWeb the Incident Information System: Sherpa Fire 4000 acres/5% containment. This morning's LA Times coverage said they were evacuating home 15 MILES away.
 

ko6jw_2

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Sherpa radio freqs.

Los Padres National Forest is running communications.

Command is Forest Net Tone 16 (Santa Cruz Island repeater)
Admin Net is being used for other fire traffic in the forest.
Forest net 3 and 4 are tactical channels (simplex)

I can't hear Santa Cruz here so I'm listening to the link repeaters.
406.325 Forest Net
408.9875 Admin Net

Air ops are on a variety of frequencies.

Helibase is at Santa Ynez airport:
163.100 is FM freq.
125.325 temp control tower and 122.800 unicom.

Air ops:
122.925 vector
135.975 vector
168.650 Nat'l Flight Following getting a lost of use.

The fire is over the ridge from me so I can't hear other tacs and a/g freqs. very well.
 
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ko6jw_2

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Additional frequencies

Helicopter vector is 118.1750

Fixed wing air tac is NIFC Air Tac 2 169.1500

Now dropping retardant to protect radio sites on Santa Ynez and Broadcast Peaks.

Many govt. and ham sites on SY Peak!!
 

kma371

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I can't hear Santa Cruz here so I'm listening to the link repeaters.
406.325 Forest Net
408.9875 Admin Net

Air ops are on a variety of frequencies.

Just want to confirm is there actually a 103.5 PL on those?
 

ko6jw_2

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Link repeaters

The link repeaters have been around for decades. In fact, there used to be more of them. They are a backup system to microwaves. The forest net link repeats nearly all radio traffic in the forest (repeater or simplex) on the VHF forest net. Likewise with the Admin. Net (formally called the service net). Very useful for monitoring fires outside the local area. Quality is sometimes sketchy, but it's better than nothing.

Yes, they both use a PL of 103.5.

I was told by a friend who was a radio technician with Los Padres that they would go away at some point. However, they got new frequencies and new transmitters - so they will be around for a while I hope.

There used to be an air net link that repeated 168.625 - the air dispatch frequency at the time. You could hear aircraft and tanker bases all over the South Zone (now South Ops). Gone for years.

There was also a zone net link that was basically an intercom between all South Zone dispatchers. Also long gone.
 

kma371

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Yea I think those are the only ones left. Just wanted to confirm the PLs for the DB. Thanks!
 

SCPD

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The link repeaters have been around for decades. In fact, there used to be more of them. They are a backup system to microwaves. The forest net link repeats nearly all radio traffic in the forest (repeater or simplex) on the VHF forest net. Likewise with the Admin. Net (formally called the service net). Very useful for monitoring fires outside the local area. Quality is sometimes sketchy, but it's better than nothing.

Yes, they both use a PL of 103.5.

I was told by a friend who was a radio technician with Los Padres that they would go away at some point. However, they got new frequencies and new transmitters - so they will be around for a while I hope.

There used to be an air net link that repeated 168.625 - the air dispatch frequency at the time. You could hear aircraft and tanker bases all over the South Zone (now South Ops). Gone for years.

There was also a zone net link that was basically an intercom between all South Zone dispatchers. Also long gone.

Let me describe what UHF link frequencies do just to make sure there is accuracy on these pages. Remote base stations are regular base stations, just like a person would find in a simple radio system such as in a small town where the antenna on the roof allows the base station to hear all the radio traffic in town without the need for a repeater. Long ago, radio systems, especially those that don't cover a lot of area or rugged topography, operated on one simplex radio frequency. If a city was too large for all the mobile radios to be heard by the base station at the police station a base station was installed on top of a building or peak to take advantage of the increased coverage that a high place allows. Now, the base station and police station need to be linked together. Sometimes the solution was to do so using phone lines. A control console transmitted the voices onto a phone line, the phone line dumped the audio onto the remotely located base station, which then transmitted the audio on the radio frequency.

There was a disadvantage to this, the police station could hear all the cars, but the cars could not hear each other if they were located some distance apart. Also, if the area could not be covered by one remote base because some of your mobile units were located on the back side of a mountain ridge. The solution would seem to be another remote base and in some big cities that could be done. But, how about a large area where there weren't any phone lines close enough to hook into? The repeater was the solution as the mobile unit on the other side of the ridge could transmit to the repeater on one frequency and the repeater would then transmit back to the remote base near town on the other frequency. As the coverage area of radio systems expanded, the location of phone lines became a limiting factor. The solution was to replace the phone lines with radio links. That allowed that original remote base station to become the hub of a radio system, communicating to distant remote bases without the need for phone lines. As long as the remote base at the hub could "see" (or could "talk to") all the other radios in the system it could control the entire radio system.

In large cities radio frequencies began to become insufficient to cover the radio systems and all the links so some very high radio frequencies 1,0000 MHz and greater were installed to replace the link frequencies so free them up to build new radio systems. These so called "microwave" frequencies don't carry very far when used for mobiles and bases so they need their energy focused on a narrow path, thus carefully aimed dishes are used. Another factor with lower frequencies is they can be affected by weather and microwave not so much, so microwave provides the clearest signal possible. One disadvantage to microwave is that it requires a better quality power system and the older sites without commercial power aren't as dependable. Solar power and batteries are not really suited to microwave stations, although in the last ten years some microwave sites are being developed absent commerical power, although it is not the preferred solution.

Now a UHF link utilizes a beam antenna that focuses the signal into a narrow path, but nearly as narrow as microwave dishes do. Common terminology the line between the antennas at each end of a microwave path or UHF signal is a hop.

Now, how does all of this apply to the Los Padres National Forest? Well, in order to switch to microwave links a lot of money must be spent. On some National Forests in California it made little sense to build a federal system that duplicated a network the state had already installed. So the feds ended up leasing microwave circuits from the state. As money has become tighter, rather than replace more links with microwave, UHF links have replaced some of the microwave circuits or hops. UHF is also able to tolerate some intervening topography and vegetation better than microwave. The federal government has 406-420 MHz assigned to it and the feds use that band for links and for mobile radio communications in large cities. VHF is preferred for rural area communications and the feds have 162-174 MHz assigned to it.

The Supervisor's Office of the Los Padres National Forest is located in Goleta and dispatch is located In Santa Maria. One or both of these are linked with a single microwave hop. The hub remote base for the southern end of the Forest is on Santa Ynez Peak, which is not a repeater, but is a remote base. This remote base receives the output frequency of the repeaters and transmits the input frequency and the link frequency also passes on the subaudible tone (PL) selected by base consoles at fire stations, ranger stations, the Forest Supervisor's Office and dispatch. In this way the remote base is acting like a mobile or handheld radio located where the hub remote base is located and one repeater is selected for use at one time. If a scanner listener is somewhere near the hop of a UHF link the advantage is that the scanner will receive everything the remote base and dispatch is hearing. Thus, when I visit a family member in the Santa Barbara area I can hear all the south end repeaters, such as Frazier Peak, that I would not otherwise be able to hear from there.

I don't know how the repeaters on the Monterey Ranger District are linked to the southern end of the Forest. It could be on the state's microwave system on multiple hops or it could be many hops of UHF links. I suspect the first as the signal quality would be better over a number of microwave hops than of UHF hops. I don't know if there is a hub remote base on that district, but I think not.

It is not possible for the hobbyist to receive the microwave links. Hobby grade microwave receivers are not made and in addition one would have to have an antenna aligned to receive the vary narrow signal. This narrow signal does not refer to bandwidth, but to wavelength. The higher the frequency the shorter the wavelength.

I know this is long, but this is not a simple topic.

One last little bit of trivia, Santa Ynez can also transmit and receive on the repeater output frequency. If a mobile unit is within range of Santa Ynez and can't bring up a repeater they switch to simplex operation on the repeater output frequency, select Tone 8 (103.5) and speak with ranger stations, etc. without the use of a repeater. Thus you might hear "Los Padres" answering a mobile unit and not hear the mobile unit at all. However, if the UHF link for Santa Ynez is heard, the mobile unit's traffic will be heard.
 

SCPD

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The Los Padres National Forest is the most spread out National Forest in California, with lands just south of Carmel in the north and south of Lake Piru in the south. One Air Guard remote base cannot cover the entire forest. The forest does have a Air Guard remote base on Santa Ynez in any case, but I don't know how it is linked. It does not have a National Flight Follow remote base and is the only forest in R5 not to have one.

I just reviewed the 2015 National Interagency Aviation Frequency Guide to verify my memory of the above information. I noticed that I failed to submit some information for the database that would be of interest to those who can hear the remote bases on Santa Ynez Peak. The guide lists 170.5500 as a local flight following frequency the south end of the Forest. I'm not confusing this with 171.5500 as this is the admin net for the forest. If someone can monitor 170.5500, now would be a good time to do so. Please report back on this net to see if it is being used during this fire.

I have no idea of how this frequency's remote base is linked.
 

SCPD

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One other thought about linking on the Los Padres National Forest. Rather than have one hub remote base that controls all the repeaters with the regular VHF input/output frequencies, each repeater may have a microwave or UHF link between them and the remote base at Santa Ynez Peak. The output tone for every repeater is 103.5 so a remote base would not be able to distinguish the signal between repeaters using tones. The Angeles National Forest has a combination of both microwave and UHF links and this allows the system to differentiate what repeater or remote base a mobile unit is using.

It is also possible that many of the Los Padres repeaters might link into a forest microwave system or leased links on the state system directly to dispatch and the Forest Supervisor's Office in Goleta.

I would love to see schematics of the radio systems of the Angeles, Cleveland, Los Padres and San Bernardino National Forests. They all have a common repeater output tone of 103.5 and must all have similar combinations of microwave and UHF links.

The south and north ops dispatcher nets, which used to be heard on both VHF and UHF frequencies around the state are now both carried on microwave. As I understand it, the state's microwave backbone carries them.
 
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SCPD

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Helicopter vector is 118.1750

Fixed wing air tac is NIFC Air Tac 2 169.1500

Now dropping retardant to protect radio sites on Santa Ynez and Broadcast Peaks.

Many govt. and ham sites on SY Peak!!

One last correction. A vector in phyics is "a quantity that has both magnitude and direction." VHF-AM radio frequencies between 108 and 137 MHz are known as "Victor" frequencies, originally to distinguish them from HF frequencies. As the lines in the movie "Airplane," were pronounced:

"Roger Murdock: Flight 2-0-9'er, you are cleared for take-off.
Captain Oveur: Roger!
Roger Murdock: Huh?
Tower voice: L.A. departure frequency, 123 point 9'er.
Captain Oveur: Roger!
Roger Murdock: Huh?
Victor Basta: Request vector, over.
Captain Oveur: What?
Tower voice: Flight 2-0-9'er cleared for vector 324.
Roger Murdock: We have clearance, Clarence.
Captain Oveur: Roger, Roger. What's our vector, Victor?
Tower voice: Tower's radio clearance, over!
Captain Oveur: That's Clarence Oveur. Over.
Tower voice: Over.
Captain Oveur: Roger.
Roger Murdock: Huh?
Tower voice: Roger, over!
Roger Murdock: What?
Captain Oveur: Huh?
Victor Basta: Who?"
 

Kirk

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168.650, National Flight Following, is very much in use on this fire, including by dispatch ("Los Padres"). I can hear them from my house in Nipomo.
 

ko6jw_2

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It does not appear the 170.550 is in use as a flight following frequency. I can confirm that LP dispatch can use National Flight Following.

With regard to linking repeater sites, I just paid a visit to the old Figueroa Mountain lookout where there are Forest Net and Admin Net repeaters. There is no microwave, but there is a VHF yagi pointed at Santa Ynez Peak. There are only three commercial antennas on the lookout. There is an old copper pipe j-pole up there too, but it has no cable attached.

The remote base on SY Peak also transmits on the VHF input frequencies. I suspect that dispatch brings up Figueroa by transmitting on the input from SY Peak with tone 14.

Figueroa does not have commercial power. They are using solar. This is good because it has kept the site from being taken over by cell phone companies etc.
 

SCPD

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168.650, National Flight Following, is very much in use on this fire, including by dispatch ("Los Padres"). I can hear them from my house in Nipomo.

The 2016 National Interagency Aviation Frequency Guide states "Flight Following is conducted on Forest Net. Los Padres NF does not have National Flight Following except on the Mt. Pinos (South) District." The guide does not identify what site the NFF remote base is located on. I would guess that it might be Mt. Pinos (Abel) or Frazier Peak if the guide is accurate. It seems unlikely that either could be heard from Nipomo and Santa Ynez and the Santa Ynez Peak could. The guide must be inaccurate.
 

SCPD

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It does not appear the 170.550 is in use as a flight following frequency. I can confirm that LP dispatch can use National Flight Following.

With regard to linking repeater sites, I just paid a visit to the old Figueroa Mountain lookout where there are Forest Net and Admin Net repeaters. There is no microwave, but there is a VHF yagi pointed at Santa Ynez Peak. There are only three commercial antennas on the lookout. There is an old copper pipe j-pole up there too, but it has no cable attached.

The remote base on SY Peak also transmits on the VHF input frequencies. I suspect that dispatch brings up Figueroa by transmitting on the input from SY Peak with tone 14.

Figueroa does not have commercial power. They are using solar. This is good because it has kept the site from being taken over by cell phone companies etc.

I did not mean to imply that all repeaters would have microwave links. It is likely that the Los Padres uses a combination of linking methods. Those methods might be:

1. VHF control using the repeater input frequency with PL's from the Santa Ynez remote base. This is likely in use for repeaters where no commercial power is available.
2. UHF links between Santa Ynez and the repeaters, both where commercial power is available and where it is not. This seems unlikely as this adds a layer of equipment and the need for many UHF frequency assignments. The Toiyabe National Forest in eastern California and Nevada uses this method, linking each repeater with UHF to the nearest microwave remote base.
3. Where commercial power is available microwave links between a hub, likely Santa Ynez Peak and the repeaters. Frazier Peak is an obvious choice for one repeater that is probably linked this way. This would be a federally owned and operated system.
4. Microwave links between a repeater and the state's microwave backbone system. This precludes the need for a hub.

Given your observations at Figueroa Mtn. #1 applies there. It is very difficult to figure out if microwave is in use at many sites due to the high number of other installations with microwave equipment. At sites where UHF links are in use the small vertically polarized antennas are not only easy to spot, but figuring out what other site they are aimed at is fairly straightforward. I think the Los Padres is a combination of #1 and #3, with some possibility that #4 is in limited use. The Los Padres is unique given how spread out it is. I think it has the greatest north south spread of any National Forest. The Custer probably has the greatest east west distance and it has now been combined with the Gallatin so the distance is even greater.

All of us would love to see UHF only linking from a single hub we can receive. Prior to the narrowband implementation in 2004 the Inyo National Forest had a single remote base on Silver Peak for one forest net. The downlink repeated the uplink. I had the VHF forest net locked out and only listened to the downlink frequency. I could hear everything the dispatcher was hearing and the dispatcher as well even though the UHF path was nearly perpendicular to my location. I could hear mobile units on the Kern Plateau, some 125 miles to my south. Now the forest has two forest nets and the south forest net remote base is on Mazourka Peak, which I cannot receive. The north net remote base is still on Silver Peak, but the uplink is not repeated on the downlink frequency.

This fire continues to be driven by sundowner winds, a local phenomena and that makes this fire a tough one as it drives the fire off the forest and down into structures. I recall the Paint Fire in the 80's where the sundowners were very strong.
 
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