LPNF Forest Net Repeater Input

iscanvnc2

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Conformation requested for the following apparent change in Los Padres NF Forest Net repeater
input frequency before submission to RRDB.

From 164.9125 to 164.8250.
The repeater output is 170.4625

This has been noted here in Ventura for the last several weeks.
 

KK6ZTE

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Negative. Are you using a commercial radio or a scanner to verify?

We would have gotten a major notice and opportunity to reprogram every fire radio in a hundred mile radius if this was the case. This would have been a very big deal, and certainly wouldn't have happened during fire season.

164.825 is LPF Service Net input, paired with 171.500 output
 

iscanvnc2

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Thanks for your response, KK6ZTE.

RRDB shows Service Net input is 164.150 paired with 171.550 (not 171.500); verified by listening

For several days of morning & evening weather/status reports this was my 3 scanner setup: (1) 170.465 output, (2) 164.9125 listed &previously verified input, (3) 164.825 questionable new input.

Result: 164.9125 nothing. 164.825 the same as 171.550 preceding it by a fraction of second as would be expected of a repeater.

I understand your position, but what I've demonstrated I'd need to be discredited by someone in this area by duplicating my situation.
 

norcalscan

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For several days of morning & evening weather/status reports this was my 3 scanner setup: (1) 170.465 output, (2) 164.9125 listed &previously verified input, (3) 164.825 questionable new input.
What you are hearing are simulcasted transmissions across multiple nets. USFS often does this for morning reports, fire weather broadcasts etc across multiple tones. That way on large forests that can't hear a single transmitter, they might choose a northern tone on Fire Net and a southern tone on Admin Net. They can spool up a third tone on a Service Net if needed. Stations can tune in to whichever is clearest. This avoids dispatch having to repeat it 3 times for south, central and northern ends of a forest. The database is correct. Admin Net 171.550/164.150 and Service Net 171.500/164.825

Try listening to all three outputs only and see if they are all the same during fire weather, morning check in etc. One might be scratchier than the other, typically signifying different mountain tops.
 

iscanvnc2

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I understand most of what you said.

One problem: You stated "The database is correct. Admin Net 171.550/164.150 and Service Net 171.500/164.825."
The database lists Admin Net 171.550/164.150 and Forest Net 170.4625/164.9125.
The database lists Service Net 408.9875/417.9875. (Can't receive.)

The database doesn't include 164.825.
 

KK6ZTE

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Wow. So much to unpack.

I guess being in Santa Barbara County isn't close enough. And that LPF decided to secretly update Forest Net just in Ventura County without telling any mutual aid agencies that respond into the forest on an almost daily basis. I'm glad you decided to ask for confirmation before submitting to the database as this is how inaccurate info is disseminated.

In addition to what Norcalscan mentioned, Los Padres will often simulcast on more than one tone on Forest and Admin. Along the SLO/SBC county line you'll get transmitter phase noise as they simulselect multiple tones that aren't simulcast. It's usable in FM capture range but sounds like crap near the edges.

If you read the database, 408.9875 is "Service Net - UHF Repeater Link" NOT "Service Net". Service Net is indeed 171.500/164.825. It's not in the database yet. It's relatively new. This can be verified in the MACS 441-1 document which lists all of the required and recommended frequencies for Fire Service mutual aid in CA. What you're calling Service Net in post 3 is LPF "Admin Net", NOT "Service Net"

Changing the input to LPF Forest Net would require EVERY SINGLE FIRE RADIO IN THE STATE OF CALIFORNIA to update their radio plan. This would happen over months/years in addition to having the OLD and NEW frequencies in the plan during the crossover period. This happened with TNF in 2018.

I understand what you think you heard, but it's not accurate. I'm not trying to be a dick, just prevent misinformation from spreading.
 

norcalscan

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The database lists Service Net 408.9875/417.9875. (Can't receive.)

The database doesn't include 164.825.
Sorry, the DB seems to be missing the Service Net, of which your 164.825 would be the input to.

Take a listen again next time for WX briefing. Listen to all 3 inputs and all 3 outputs. That might clue you in on what nets LPF is choosing to cover each portion of the forest, at least from the Ventura end of things. I defer to the local expert of KK6ZTE who knows LPF and SBA well, but I bet you you are hearing exactly what I mention, the dispatcher simulcasting the WX on all three nets, one of which you can hear, probably using the RF input from the tower at dispatch, or a remote base, and the other two either using UHF directional links or microwave to get further north up the forest. From a scanner's perspective, I agree it would definitely appear that you found a new input to an existing output. But you have to be careful jumping to conclusions just from a scanner. Another clue, if you have the exact same radio model listening to input and output of an analog repeater, you should experience no audible latency. The fact you mentioned you hear a "fraction of a second" difference, clues me more that you are hearing two different RF systems and audio paths, that are simply sharing the same mic for that particular transmission.

You're on the right path with sleuthing and digging deep into the hobby, keep it up and don't get discouraged. But you'll find the closer your ears think you get to a truth, the more likely you'll be bamboozled by a wizard behind the curtain, a patch on a dispatch console, fancy remote bases, simulcasted audio paths, temporary audio linking by the likes of ACU-1000's etc. It's all part of the fun of the hobby.
 

iscanvnc2

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You're right, KK6ZTE. I did make a misnomer.

After 31 years as an electronic engr at Point Mugu testing sophisticated receiving systems (anti-radiation missile guidance sections, radar warning receivers, etc) I'm not easily "bamboozled".

More tomorrow? G'night.
 

KK6ZTE

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You're right, KK6ZTE. I did make a misnomer.

After 31 years as an electronic engr at Point Mugu testing sophisticated receiving systems (anti-radiation missile guidance sections, radar warning receivers, etc) I'm not easily "bamboozled".

More tomorrow? G'night.
Cool story.

I don't know where else we can go with this, but I think we've got the answer.
 

ko6jw_2

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I have begun monitoring 171.500MHz here in Santa Ynez. Historically the "Admin" net used to be called the "Service" net. Some forests do have both. I have heard no reference to it on the air. Maybe it only exists in Ventura County. The UHF links are, I believe, only transmitted from Santa Ynez Peak. I don't think you can hear them elsewhere in the LP. They are really a backup system, but they are maintained. As a piece of trivia, there used to be four UHF links - Forest, Service, Air and Zone.
 
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B

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I've been hearing the LPF on 164.825 down here in North San Diego County for over a week now...On a base, w/ external antenna.
 

iscanvnc2

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Just heard a local engine checking in on Forest Net on the established 164.9125 input thus verifying the use of 164.825 for "simulcasted transmissions across multiple nets..... for morning reports, fire weather broadcasts etc across multiple tones" per norcalscan.
 

Paysonscanner

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I've been hearing the LPF on 164.825 down here in North San Diego County for over a week now...On a base, w/ external antenna.
Hubby and I used to pick up San Diego traffic on a 8 channel crystal tuned Regency scanner where the 101 hugs the coast. We both attended Cal Poly SLO for one semester where we met. We each had a Regency, my Daddy bought me one when I went on to college. Trouble was, in college I couldn't afford to buy crystals when something new was discovered. Anyway, I'm betting you are picking up the remote base on Santa Ynez transmitting to a repeater somewhere on the forest. If you hear a tone, then you know what repeater is being worked. Believe it or not, the remote base on Santa Ynez is able to work every repeater on the forest, including those on the Monterey Ranger District. They don't have a remote base up there that is then linked south.
 

Paysonscanner

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Sorry, the DB seems to be missing the Service Net, of which your 164.825 would be the input to.

Take a listen again next time for WX briefing. Listen to all 3 inputs and all 3 outputs. That might clue you in on what nets LPF is choosing to cover each portion of the forest, at least from the Ventura end of things. I defer to the local expert of KK6ZTE who knows LPF and SBA well, but I bet you you are hearing exactly what I mention, the dispatcher simulcasting the WX on all three nets, one of which you can hear, probably using the RF input from the tower at dispatch, or a remote base, and the other two either using UHF directional links or microwave to get further north up the forest. From a scanner's perspective, I agree it would definitely appear that you found a new input to an existing output. But you have to be careful jumping to conclusions just from a scanner. Another clue, if you have the exact same radio model listening to input and output of an analog repeater, you should experience no audible latency. The fact you mentioned you hear a "fraction of a second" difference, clues me more that you are hearing two different RF systems and audio paths, that are simply sharing the same mic for that particular transmission.

You're on the right path with sleuthing and digging deep into the hobby, keep it up and don't get discouraged. But you'll find the closer your ears think you get to a truth, the more likely you'll be bamboozled by a wizard behind the curtain, a patch on a dispatch console, fancy remote bases, simulcasted audio paths, temporary audio linking by the likes of ACU-1000's etc. It's all part of the fun of the hobby.
My late Hubby has a note and a USFS electronic tech name who said the LPF has one remote base on Santa Ynez that works all the repeaters, including those up north on the Monterey Ranger District. There are no additional UHF links, no additional remote bases and no microwave. Good advice to others as for assuming they are linking inputs and outputs when they are likely hearing a multicast signal. I didn't know if they can key up the northern repeaters along with the southern ones when they broadcast the weather, but apparently so.

I have the 2020 R5 directory which says: 170.4625 out/164.9125 in, Forest Net; 171.5500 out/164.1500 in, Admin Net; and 171.5000 out/164.8250 in, Service Net. For a couple of decades or more the LPF didn't run a service net on the service net freqs, assigned to them by the region, but ran it as an admin or just an alternate command. When all the changes brought on by narrowbanding and the 2019 NTIA allocation came about, the region assigned several service net freq pairs, some new. They let the LPF use the old service net they assigned for admin and gave them a new service net pair. We used to pick up the LPF from across the valley in the Sierra Nevada foothill area. I first noticed the service net shown on a LPF group freq listing about 3-5 years ago, but I think they showed it simplex and only on the groups for the Monterey RD. It showed up this year in the directory for the first time and included a rpt pair.

I have begun monitoring 171.500MHz here in Santa Ynez. Historically the "Admin" net used to be called the "Service" net. Some forests do have both. I have heard no reference to it on the air. Maybe it only exists in Ventura County. The UHF links are, I believe, only transmitted from Santa Ynez Peak. I don't think you can hear them elsewhere in the LP. They are really a backup system, but they are maintained. As a piece of trivia, there used to be four UHF links - Forest, Service, Air and Zone.
You are correct, the UHF links only link Santa Ynez to dispatch. the Santa Barbara Ranger Station and the Forest Supervisor's Office in Goleta. The forest only has one remote base and it works all 20 of the repeaters on the forest. Some of these sites don't have repeaters on all 3 nets, only 6 do and 4 only have one of the nets. There are 7 that work all 3 nets. I'll bet every site is going to have all 3 at some point in the future as funding gradually allows. The LPF has a very heavy workload, most especially in fire management. It is the only NF in the country with 3 Type 2 helos on it.

No, the UHF links are not a backup! Dispatch in Santa Maria, the Santa Barbara Ranger Station and the Sup's Office can only work every repeater because of these links. If the links were to fail, they could only work the repeaters line of sight to the Santa Maria airport (dispatch is located there), the Santa Barbara RS east of Cachuma Lake and Goleta. This is why they have to be maintained! They have a UHF link for National Air Guard on Santa Ynez Peak, but I can't tell with what I have if that is true for National Flight Following. They have a note for that saying NFF is limited on the forest and to use forest net if unable to contact the dispatch center. They might only have a NFF base station at dispatch itself, which would only be useful for using the air attack base there. That means they have a total of 4 UHF linking pairs for Santa Ynez,: Forest, Admin, Service and Air Guard. The old Zone networks are gone, they were put on the State's microwave system 3 decades ago. I think they have full duplex on it, just like an intercom. We used to pick up both the South Zone net and the North Zone net from out home. The North Zone net used some low band freqs, otherwise I'm not sure we would have picked it up. There was a hop from Frazier Peak on the LPF and we could hear it all over the Central Valley.
 

Paysonscanner

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Also, we now have the Service Net links. Remember that the lower of the 2 freqs is the downlink and the uplink freq is always 9 MHz higher. It would be useful if someone could do some searching/sweeping in Santa Maria or Santa Barbara for the remaining links. The 12 link pairs should be tried first, they are listed in the database and I was able to obtain the list from someone last summer in California that was an independent source. I was in Mammoth Lakes last summer for a couple of months and was able to verify those used on the Inyo NF for their North, South, Service and Air Guard nets. I think 406.3250/415.3250 might be used for Air Guard all over the state, but I can't say for sure. We never had the chance to test that out on our frequent trips about the state. I would not assume that this list is complete, but who knows?
 

iscanvnc2

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The tone is 156.7 which is Torrey (Torrey Mtn), a popular location for public service xmtrs (CHP, county fire, F&G, etc) which is in the mountain range between Piru & Simi Valley. This location serves the south end of LPF.

The broadcasts are for SLO, SBA, & VNC counties.
 

Paysonscanner

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The tone is 156.7 which is Torrey (Torrey Mtn), a popular location for public service xmtrs (CHP, county fire, F&G, etc) which is in the mountain range between Piru & Simi Valley. This location serves the south end of LPF.

The broadcasts are for SLO, SBA, & VNC counties.
Here is a list of the repeaters :

T = Tone, F = Forest Net, A = Admin Net, S = Service Net, RD = Ranger District

List is arranged from north to south---all have T8 on output

Chews Ridge T10---F, A
Anderson Peak T13---F, A
Cone Peak T8---F, A, S
Alder Peak T4---F, A, S
Manuel Mtn. T4---F (on Monterey RD only)
Calandra T15---A only
Tassajara Peak T9---F, A
Black Mtn. T5---F, A , S
Plowshare T11---F, A
Tepusquet Peak T12---F, A
Figueroa Mtn. T14---F, A, S
Santa Ynez Direct T8---Remote Base-Use Forest Net Simplex (Channel 1) and Admin Net Simplex (Channel 7) to call dispatch. Works on the Santa Barbara RD only
La Cumbre T3---F, A, S
Mt. Pinos T7---F, A, S
Frazier T1---F, A
Sisar Peak T2---F, A
Torrey Hill T6---F, A, S Ojai RD
Piedras Blancas T6--F, A Monterey RD
Santa Cruz Island T16---F only
Tranquillon Mtn T16---S only
Nordhoff Peak T15---F only, Ojai RD only

They lied, this is not completely a north-south listing. The last 4 repeaters are somewhat new, so they threw them at the end. 20 repeaters that can be worked from one remote base--amazing! Especially the Monterey RD repeaters. I think this is largely due to the coastline continually moving east as you move south. Open water is a great extender of coverage.

Tones

1--110.9
2--123.0
3--131.8
4--136.5
5--146.2
6--156.7
7--167.9
8--103.5
9--100.0
10--107.2
11--114.8
12--127.3
13--141.3
14--151.4
15--162.2
16--192.8

The first 8 were standardized in California sometime in the late 70's or early 80's. FIRESCOPE probably got involved. The list was expanded to 16 sometime in the early 90's. This to the best of my memory. Sometime around 2010 or later, this list, along with its numerical labeling was issued as a national standard by NIFC. Some regions are still using non-standard tones and some label them starting with the lowest freq first, 100.0, then 103.5, etc. The most common non-standard tone is 179.9. Varying the labels can cause some mix ups. Someone coming from R5 and other units in other states that have them entered with the national standard might be told, "Forest Net Tone 1" and their radio will transmit 110.9 and the repeater recognizes 100.0 only. I don't understand why other regions and units have to mix this all up. I think it will change slowly and if NIFC issues mandatory compliance it will go faster.

In the last few years FIRESCOPE standardized a 32 tone list. Since the Bendix-King is the radio of choice on wildland fires and natural resource agencies and it has a 16 tone capacity use of the second 16 is not happening in the wildland community. The USFS/NPS/Cal Fire vehicles I've been in have a 16 position external tone box. NIFC has only standardized the first 16 anyway.

As you might be thinking, my late Hubby and I really got into the comm systems of land management/natural resource agencies. We hiked and drove in remote places as much as we could. We found it interesting and beneficial to understand the comm systems we would encounter when we traveled. I know that this might seem as though a woman would not be interested. Late Hubby and I were interested in each others pursuits. I could almost hike as well as he could and we almost always went together. Listening to the radio systems was fun and at times useful. BTW, I taught him to sew!

I hope this post is useful for some people.
 

Paysonscanner

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The locations of some of the new repeaters might not be widely known. I did a little research to update the LPF repeater map I have. Manuel is just east of Big Sur, on a ridge whose base is located near Big Sur. Tranquilllon is located on the Vandenberg Air Force base, southwest corner. Nordhoff Peak is located just west of Sisar Peak. It seems like Manuel and Nordhoff Peak are very close to other repeaters, but may provide coverage for areas in the shadows of those other repeaters. I had no trouble doing a Google search for these peaks, in case you are interested in finding all of the on maps.
 

ko6jw_2

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I spoke last night to a fellow ham who is the chief of a local fire department and a cooperator with the LPNF. He has the communications plan for LPNF dated 03/18/2020. He says there is no separate "service net." He programs all of his department's radios and would certainly know.

Here in Santa Ynez I have monitored 171.500MHz and have heard no traffic. I have heard traffic on 164.825MHz, the supposed input for the theoretical service net. However, that traffic (afternoon weather etc.) was repeated on the Forest Net. I could hear it on the La Cumbre Peak repeater as well as on the link repeater. My friend believes that they may be simulcasting and using two input frequencies for one output on 170.4625MHz. I will monitor the other input of 164.9125MHz today to verify. Since all of the transmissions on the inputs originate on Santa Ynez Peak and I have line of sight here, I should be able to hear any transmissions.

The only reference to a service net in the comm plan are fire camp nets and these are portable repeaters that would only be deployed in a major fire.

Finally, interesting as this discussion may be, there is little reason to listen to input frequencies and some reasons not to listen. For one thing you will only hear the dispatch center or nearby mobile units. For another reason, you will hear noise from weak signals which is of no use to anyone.

I will also do a search for additional UHF links. However, my best information from another ham who was a contract radio technician for LPNF is that there or only the two we know of. He gave me those frequencies when he installed them several years ago and I put them in the RR database.
 

ko6jw_2

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Morning weather is being simulcast on 164.825MHz and 164.9125MHz from Santa Ynez. Output on 170.4625MHz and 406.325MHz link. Searching link channels today. Only the usual suspects so far.

The Angeles NF service net is 171.500MHz. This could be heard in Ventura County. The input is 164.825MHz. In fact this pair is in use in other national forests. Maybe one day in the LPNF?

It has been suggested that the dual input frequencies may be an attempt to mitigate phase distortion problems which have plagued the LPNF system for a long time.

Could LP be bringing up ANF repeaters? Have to check PL's later.
 
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