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The Hidden Peak Repeater
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About the Hidden Peak Repeater:
The Hidden Peak (located at the top of the Snowbird tram) is the hub
of the Intermountain Intertie. This system (occasionally referred
to as the "Snowbird Link System") is a more-or-less
informal
collection of repeaters located in northern Utah/Southwestern Wyoming,
many of which are supported in part by the VHF Society. This
system
is a hub-and-spoke system, with the Hidden Peak site as the hub. For
a detailed map of this system, go to The
Intermountain Intertie page.
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This repeater first went on the air in 1974 and it still operates from the same site and on the same frequency. During the intervening years, a lot has changed with the repeater: It is now the Utah hub of the Intermountain Intertie and from this site, it directly connects the 147.12, the 146.86, the 147.02 repeaters together, and it also has links that connect it to the repeaters in the southern part of the state and to the Idaho linked system. You may be interested in visiting the Medicine Butte Repeater page as well.
What originally started out as a fairly simple 2 meter repeater
using
tube-type equipment has evolved into the linked system that we now
use.
It has been been built and maintained, almost single-handedly, by John
Lloyd, K7JL with support from the Utah VHF Society. Owing to this
repeater's location, it is able to cover much of the Salt Lake valley
(particularly
the western part) in addition to the so-called "high valley"
communities
like Park City, Heber, Duchesne, and Coalville, to name a few. It
is even possible to work this repeater in parts of western Colorado,
part
of southwestern Wyoming, and even as far south as Price, Utah, if one
is
in the right location and has a good signal. Its coverage of the
eastern benches of the Salt Lake valley is somewhat limited, owing to
the
fact that Hidden Peak is several miles in from the front range of the
Wasatch
and is thus shadowed.
Hidden Peak (or "The Top of the Snowbird Tram")
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One of the great advantages of mountaintop sites is that, well, they are atop mountains: They can have excellent coverage, and the view from the site is often spectacular.
One of the great disadvantages of mountaintop sites is that, well, they are atop mountains: In the Utah winter, most mountaintops are inaccessible except by helicopter, skis/snowshoes, and in some cases via snowmobiles and snowcats.
The Hidden Peak site is rather unique among mountaintop sites in
that
it is rather easier to access the mountaintop during the winter than it
is during the summer. You see, during the winter, the tram runs
very
frequently: Every time there are enough people to fill the
gondola,
it's on its way. During the summer, the tram runs far less often
and one must often wait quite a while for a ride up or down.
Despite
the relative ease of access during the winter, there is no doubt that
it
is much more comfortable to work on the repeater and/or its antennas
during
warm weather. At 11,000 feet, winter winds are always blowing and
the wind-chill is, well, chilling!
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In addition to this UHF repeater, there are two additional links on
the site: A point-to-point link goes south to Frisco Peak (north
of Cedar City) and another link goes north to provide connectivity to
the
Idaho system. Interestingly, there is a mountain directly in the
path of the south link (Lone Peak is in the way, and it is over 200
feet
higher than Hidden Peak.) It was discovered that only the
125cm band would work for this link (other bands were tried!)
and
even though it works, signals are extremely weak. To get the best
possible signals this link uses beams and fairly high transmit power on
each end, low-noise GaAsFET preamplifiers and low-loss 1/2 inch
semi-rigid
coaxial cable. As a result of all of this effort, the path has
proven
to be quite reliable.
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As with any repeater system, failures do occur occasionally. Several years ago, a direct lightning strike damaged/destroyed several of the radios in the repeater system. The entire rack of equipment had to be hauled down to the valley (to John Lloyd's house, actually) and the repeater was, in essence, rebuilt. More recently, a power supply failed. This particular Motorola power supply employed a switching regulator as part of its design and it began to buckle under the repeater's normal load. Finally, a component failed such that the power supply wasn't able to start up properly, so it would shut itself down after such an unsuccessful attempt, only to try to start again. Each time it went through this cycle, it sent a voltage surge through the system which eventually destroyed some on-board regulation circuitry on several of the repeater controller's boards and the power amplifier for the link transmitter that connects Hidden Peak to the southern part of the state.
The "SNOW" Node
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The high location of Hidden peak makes it both a good and bad location for packet nodes: Good, in that it can cover a lot of area: It can see many other distant mountaintops and can thus provide much-needed connectivity around the region. Bad, precisely because it covers so much area. Since it sees so much, it hears almost everything on the frequency, causing some severe congestion. For this reason, it is urgently requested that, unless you have no other choice, you should avoid using the SNOW node directly and connect through it with another node.
Another way that congestion is being combatted is by putting a UHF
9600
baud packet node at the site as well. This provides a backbone
connection
to/from the node without unnecessarily tying up the
already-busy
2 meter 1200 baud frequency.
"How much area does the Hidden Peak repeater cover?"
Determining the coverage area of a repeater in mountainous areas
(like
Utah) isn't a straightforward or accurate process. The very best
way is to simply put a transmitter on the site in question and then see
where it covers. In the case of the Hidden Peak Repeater, there
has
been 25 years of experience with its coverage abilities, so these
parameters
are quite well known. More recently, computer signal strength
predictions
based on actual terrain modeling have become available. These
take
into accout the existance of the mountains and their predicted effects
on the signal strength at the frequency of interest.
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On the map note that, at first glance, the "yellow" colors around the edges and the brown/orange colors next to the green areas near the middle may look similar. Keep this in mind to avoid confusion.
For more information about the, go to the UARC Scott's Hill, Predicted Signal Contours page. This page also predicts signal strengths from Scott's Hill (to the north and east of Hidden Peak) and Farnsworth Peak (southwest of Salt Lake, in the Oquirrhs.)
IRLP connection into the
Intermountain Intertie:
The "IRLP" is the Internet Repeater Linking Project - an affiliation of repeater and radio systems that provide connectivity to each other via the internet. This system allows repeater and amateur radio systems worldwide to interconnect with one another. For more information, go to the IRLP web page. For specific node status, go here.
There are several points where it is possible to connect into the Intermountain Intertie via IRLP or even "I-Link" - but most of these are through other systems whereby a radio may be remotely controlled to connect to an Intermountain Intertie repeater.
IRLP Node 3660, however, is intended to provide a direct connection into the Hidden Peak hub repeater. It should be noted that although the computer hardware is present, it is not on the air! That is, even if you connect to it, you are talking to nothing - as no radio has been connected... yet. This continues to be an ongoing project.
If you have any questions about this node, please contact John Lloyd, K7JL.
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Questions, updates, or comments pertaining to this web page may be directed to: uvhfs@utahvhfs.org
This page was last updated on 20030417
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