South Zone 166.5625?

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Progline

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I copied South Zone today calling Los Padres on 166.5625 to discuss ordering that day's tankers. I did not hear the LP reply, and from where I was, I should have. Later in the day, South zone called Sequioa NF to discuss need to divert a tanker from Gap Fire to an incident they had. I heard no reply either.

Is 166.5625 the input to a repeater? I am curious why I only hear one side of the conversation...I've listened to this freq for a few fire seasons, and have never heard anyone answer them.

-Rob
 

Progline

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Google may be my friend, but I'd rather hear from the expertise of those on this board who might acutally know.

I have monitored 164.9125, heard zilch on that one too.

What i don't get is that I hear him at the same signal strength when he's talking to Los Padres or Sequioa. I'm obviously hearing him from the same mtn top transmitter (PL 103.5 BTW).
 

SCPD

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I copied South Zone today calling Los Padres on 166.5625 to discuss ordering that day's tankers. I did not hear the LP reply, and from where I was, I should have. Later in the day, South zone called Sequioa NF to discuss need to divert a tanker from Gap Fire to an incident they had. I heard no reply either.

Is 166.5625 the input to a repeater? I am curious why I only hear one side of the conversation...I've listened to this freq for a few fire seasons, and have never heard anyone answer them.

-Rob
I have an old plan that outlines the system. It would help me if I knew where you are located. If I have a general idea I will be able to explain why you didn't hear replies. There are two 160 MHz frequencies and two UHF frequencies in the system. There is a strong possibility that the UHF frequencies are different than the plan. I don't have access to the plan right now as I have company and my office is currently being used as a bedroom. I should have access to the information tomorrow.
 

commstar

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Google may be my friend, but I'd rather hear from the expertise of those on this board who might acutally know.

I have monitored 164.9125, heard zilch on that one too.

What i don't get is that I hear him at the same signal strength when he's talking to Los Padres or Sequioa. I'm obviously hearing him from the same mtn top transmitter (PL 103.5 BTW).
Please allow me to rephrase and resubmit:

Hey, I found this site via Google search while looking for something else for myself- it lists information that may be of interest to you:
http://www.police-scanner.info/wordpress/

It seems to indicate that 166.5625 is an input to 164.9125, and as South Zone.

Hope the information helps and pleasant monitoring.
 

Progline

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Ex Smokey, I am located in the northwest San Fernadno Valley. I verified today (when so zone was talking with the LPNF) that what I heard was not being repeated on 164.9125, or anywhere from 415-416MHz.

It's a mystery to me.
 

SCPD

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You must have been receiving the Santiago Peak to Frazier Mountain link that is on 166.5625 MHz. Frazier transmits back to Santiago on 164.9125 MHz. Frazier also transmits to Santa Ynez on 164.9125 MHz also and Santa Ynez transmits on 166.5625 back to Frazier. The remainder of the linking is via 400 MHz frequencies. Santiago used to be down linked to the San Bernardino Federal Interagency Communications Center, the Monte Vista ECC, and South Ops in Riverside with 415.525 MHz and up linked from those locations with 411.525. The Angeles NF used to be linked the same way when they were in Pasadena and later Arcadia, but now that they are over the hill in the Antelope Valley, I'm not sure how they are linked. They might be like the Inyo NF and are linked via the state's microwave system. Santa Ynez Peak was linked to the Los Padres NF dispatch center via the same UHF frequencies. The dispatch centers in Porterville (Central Calif. BLM and Sequoia NF), Visalia (Tulare Unit CDF), Clovis (Fresno-Kings Unit CDF and Sierra NF), and Sonora (Stanislaus NF) were connected to Frazier in the same way. I'm not sure of San Andreas (Tuloumne-Calaveras Unit CDF) and Mariposa (Madera-Mariposa-Merced Unit CDF) use the state microwave or are linked to Frazier on the 400 MHz frequencies.

You may be able to copy the 415.525 MHz Santiago Peak downlink from your location. I know I pick up 440 MHz ham repeaters in the northern San Fernando Valley on my mobile when I'm down there. Its a bit scratchy in the northern part of the valley, but then I'm using a hatchback lip mount with only a 17" dual band antenna.

The up link frequency shows 411.525 as the plan I have is much older than 2005, the year the federal government began mandatory narrow band and changed the spread between the up and down links from 4 MHz to 9 MHz. So if 415.525 is still the down link then 406.525 would be the up link. Recently, (as of 1/2008) the federal government's National Telecommunications and Information Administration (NTIA) Redbook contained wording to the effect that the down link is to be the lower of the two. If that change has been made to the South Ops Net, then 406.525 MHz would be the down link and 415.525 would be the up link. It is possible that this change has not been made yet as it has only been about 1-2 months since the UHF linking system was updated here on the Inyo NF so try both 415.525 MHz and 406.525 MHz for awhile first.

The other possibility is that a completely different pair is now currently in use. If you don't hear anything on 406/415.525 then try searching the entire 406.1125-410.9875 MHz portion of the UHF band and you may get something. The up link used to be repeated on the down link, so you should be able to hear everything on the South Ops Net if you can, in fact, receive the UHF downlink. If not, then I would suggest you try the 164.9125 Frazier to Santiago link. I don't think you will be able to copy it from your location as you are probably in a shadow for Frazier. I know I can't receive or key up any ham repeaters on Frazier from the northwest portion of the San Fernando Valley. In addition, the VHF signal from Frazier to Santa Ynez and Santiago on 164.9125 is shown in the plan as being horizontally polarized so you may not get very much penetration or ground level signal in the shadow you are in. Although it is not specifically addressed in the plan, I believe the down link is transmitted from Santiago Peak on an omni-directional antenna.

If there is anyone located in the L.A. Basin (from Oceanside to West L.A. and out to San Bernardino and Riverside) that can try the above 400 MHz frequencies and see if they can copy South Ops, I would appreciate it. This is a good frequency to listen to during fire season, although computers and phones are quite often used to relay orders between the dispatch centers and South Ops. Even so, the last time I was down in southern California and heard this net, the traffic certainly added to my understanding of a number of incidents being worked on the Los Padres, Angeles, and Cleveland National Forests.
 
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Progline

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ExSmokey, if they are talking back from Frazier, that could indeed explain it. You are correct, I am in a shaded area for Frazier coverage. Frazier generally can't be heard until the south end of the valley. this is true for Moorpark & Simi Valley - they are shadowed, but 1000 Oaks is not.

I'll put the 164.9125 in the scanner in the car, if I hear them when I'm mobile, I'll reopen this thread and post it.

Thanks again!
 

kd6ecz

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If there is anyone located in the L.A. Basin (from Oceanside to West L.A. and out to San Bernardino and Riverside) that can try the above 400 MHz frequencies and see if they can copy South Ops, I would appreciate it. This is a good frequency to listen to during fire season, although computers and phones are quite often used to relay orders between the dispatch centers and South Ops. Even so, the last time I was down in southern California and heard this net, the traffic certainly added to my understanding of a number of incidents being worked on the Los Padres, Angeles, and Cleveland National Forests.
I'm located in Rancho Cucamonga and just about 10 minutes ago I heard radio traffic on 415.525. I'm not 100% sure but it sounded like it was South Ops. I still hear South Ops on 166.5625 from time to time as well. These frequencies don't seem to be as active as they were when I first started monitoring them back in the early to mid 1990s. For a couple of years I wasn't hearing anything on them but just in the past few months or so I have been catching South Ops radio traffic again.

Edit:
I just seconds ago heard some more radio traffic on 415.525 between South Ops and Los Padres National Forest.
 
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SCPD

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I'm located in Rancho Cucamonga and just about 10 minutes ago I heard radio traffic on 415.525. I'm not 100% sure but it sounded like it was South Ops. I still hear South Ops on 166.5625 from time to time as well. These frequencies don't seem to be as active as they were when I first started monitoring them back in the early to mid 1990s. For a couple of years I wasn't hearing anything on them but just in the past few months or so I have been catching South Ops radio traffic again.

Edit:
I just seconds ago heard some more radio traffic on 415.525 between South Ops and Los Padres National Forest.

Up until 1998 the Forest Service used a Data General computer system that could not employ any software except that specifically written for the Data General operating system. This limited the use of computers in making a tracking orders to and from South Ops, especially when they came from non Forest Service dispatch centers. South Ops and the Forest Service dispatch centers did have a limited number of "real" computers during those times so the traffic volume was somewhat reduced in the 1990's as compared to the 1970's and early 1980's.

Sometimes when there are questions regarding orders or a discussion about them, it is easier to use this "intercom system" (the South Ops net) than to pick up a phone and talk about it. This is when you hear something on this net. Especially when the person working a console for a Forest or CDF is busy and someone else is answering the phones because of a high volume of radio traffic. At times one person in a dispatch center is assigned the job of relaying all orders to the appropriate Geographical Area Operations Center (GACC) (North and South Ops are just two of 11 of these centers) and that person is probably the one assigned to monitor the GACC dispatchers net. I'm not aware of any other GACC except the two in California having a dispatchers net or intercom that uses VHF/UHF radio frequencies. North Ops has a net similar to South Ops except it uses low band VHF frequencies. The hub mountain for this system is on Saint John's Mountain or Mount Saint John's on the Mendocino National Forest.

A few years back some direction came out indicating that high band VHF frequencies were not to be used for point to point communications. The South Ops net continues to do so. In addition KD6ECZ's observations clearly show that 415.525 continues to be the down link frequency rather than the 9 MHz lower frequency as specified in the January 08 NTIA Redbook. If anyone stops hearing traffic on 415.525 then 406.525 should be monitored to see if the down link has been moved. I suspect it will happen after fire season is over.

KD6ECZ, it would be good if you start listening on 406.525 as I'm thinking it might be possible that from your location you might be hearing the up link from Riverside (where South Ops is located). If you heard both the Los Padres and South Ops on 415.525 then it is still the down link as this system was designed to have the down link repeat all the up link traffic.
 

kd6ecz

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I'll add 406.525 to my scanner and see if anything pops up. I mainly run around the Inland Empire with my Pro-96 with the rubber duck antenna connected so I may or may not hear anything.

South Ops is located in Riverside isn't it? I work in San Bernardino so I'm pretty close to them during the week if that's the case.
 

Teotwaki

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Today I am hearing fire fighting air ops on 164.9125 with 103.5 PL in Huntington Beach and it sounds like a repeater, not simplex. Am trying to see if I can hear a VHF input or 400MHz link also.
 
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Mike_G_D

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415 links (and NOT the sausages!)

Exsmokey,

For what it's worth, here is what I have heard in north Carlsbad:

415.525MHz - very weak but heavy traffic over the last few days; seems to be helicopters talking to each other and coordinating fire retardant drops but the signals are not clear here and are hard to listen to over extended periods.

415.450MHz - repeats Cleveland NF Forest net on 168.75MHz with the same tone; weak but readable.

415.475MHz - seems to be referring to San Bernardino NF and is stronger in my area than the Cleveland NF link noted above. However, oddly, I cannot figure out what it is repeating as it does NOT (at least in the times I have heard traffic on it) repeat the SB NF Forest Net traffic on 171.475 which I get quite well here (on the VHF frequency). I thought that it might be repeating the Admin net on 172.225MHz but have not been able to confirm that yet as I haven't heard anything on 172.225MHz to compare it with.

171.425MHz - seems quite strong and seems to my untrained ear to be referring to forest service-type traffic. My old frequency sources list it as a Department Of Agriculture Soil Conservation frequency so maybe that is what it is but it sure sounds more like what I pick up on the Cleveland and San Bernardino NF's channels. I will have to monitor for awhile and see if I can deduce this further. With you information and all of the Federal reshuffling of frequencies going on I am wondering if its usage changed recently - maybe the new SB NF Admin net since I seem not to hear anything on the posted 172.225MHz frequency?

And as an aside, I am picking up quite a lot of dead carriers being keyed up on various frequencies between 406MHz and 411MHz. Also, one in particular appears to be shifting in frequency between 406.5MHz and 406.525MHz - I need to verify this with my ICOM communications receiver to make sure it's not an artifact of my scanner but it doesn't sound like an out of band signal to my ears (I have a fairly strong RF background as an engineering technician, BTW). This one aside, I am thinking that some of these other dead carriers keying on and off might be from new repeaters being brought online - as you have stated the new ones in this band should have outputs in this range. And I have not gotten any LTR info from these carriers in case anyone asks plus they seem more erratic than an LTR signal in terms of their on-off timing.

Now that I have finally gotten a new scanner (PSR-500) I am getting back into the hobby somewhat and am fascinated by posts such as yours. Thank you for them! I will keep monitoring and post anything of major interest.

-Mike
 

Mike_G_D

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171.425

WB,

Thank you - you are correct. I just confirmed it. 171.425MHz is the input to Cleveland Forest Net 168.75MHz. But where did you see this listed? I knew they were changing as per information from, I believe, Exsmokey on this site but have yet to see any updated info. I've checked my usual 4 sites, including this one, and all still list the old input frequency. Would really like to know where the new info is listed!

Also, I've confirmed that the inputs to the Cleveland Admin Net and the SB NF Forest Net have not changed from the listed frequencies, at least as of today. But then you likely know that!

Also, I've finally confirmed that the 415.475MHz link I have heard is definitely repeating SB NF's Admin Net of 172.225MHz and NOT their Forest Net. Haven't found a 415MHz link for that yet if it exists nor have I found one for Cleveland's Admin Net.

-Mike
 

silverspy

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There was a post about a month ago in the California forum entitled, "USFS/BLM Load Out", which is where I obtained the info for the new Cleveland NF input. The person that posted the thread put an asterik next to the Cleveland frequency, to indicate that the input had changed. I can't figure out the logic behind all these frequency changes in the federal realm. For example, the BLM in Idaho and Utah changed to completely new frequencies. I know in Idaho, it was because the BLM outputs were on DOJ frequencies, but it definitely is a treasure hunt. If you are interested in USFS and BLM in California, I have found the best source is a book entitled "Government Radio Systems, Federal Radio Systems" written by Robert Kelty. The book is about $20.00 and you can get it from Ham Radio Outlet. I know the Mountain View store usually stocks it, but you might also try Burbank or Anaheim. Just make sure that you ask for the 2007 or 2008 edition, as the information changes rapidly. Hope this has been of help.
 

Mike_G_D

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Fed musical freq.'s

WB,

Yes, thank you! I will check that out. I think the federal government is re-ordering frequency usage in response to usage of "narrow-band" and P25 technologies in order to better consolidate user categories and accommodate more channels.

I have noticed and logged a large number of P25 encrypted and clear voice apparently conventional users in the 162MHz to 174MHz band in my area. At least one is on an old USFS channel according to an old listing I have. Largely, I think, it's all about cramming more users in a confined frequency space and attempting to better organize the usage (by a method only they know) while doing so. Plus, they have to deal with the lesser funded agencies (like the USFS, etc.) not being able to afford massive equipment upgrades as easily as those agencies deemed necessary to "Homeland Security" so the changes in USFS frequency usage is more piecemeal and fragmented (plus, as Exsmokey has said - you have to work around fire season and so forth).

-Mike
 

zerg901

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I think that if you hunt around in the California Mobilization Plan you will see that the South Zone Net is only used for 'initial attack' resource orders. Subsequent resource orders are done by other means (possibly, telephone, computer, or microwave). Therefore the South Zone Net might be busiest when many fires are just initially breaking out.

Does that sound about right ExSmokey?

Peter Sz
 
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