From the archive, originally posted by: [ spectre ]

Space History Buffs Try to Save Sat Dish

Mar 12, 2007   /  Aerospace Daily & Defense Report

A chance reading of a “for sale” advertisement in a weekly newspaper
has launched a group of 30 space history buffs on a mission to save
the 30-meter Jamesburg AT&T/Comsat satellite dish about an hour from
Monterey, Calif.

The dish was built in 1968 to support the Apollo 11 moon landing a
year later. Besides its commercial duties, it also played a role in
capturing and distributing images of the 1989 Tiananmen Square
protests, says Pat Barthelow, an avionics technician from Sacramento
who first noticed the ad in the Carmel (Calif.) Pine Cone and quickly
put out the word.

The weekend restorers worked over the past four months to get the dish
running. The 10-story high dish is housed in a 20,000 square foot
building, both of which are in excellent shape, Barthelow said.

But the restorers were cautious about commanding its huge drive
mechanism until they understood the computer code of its Vertex-RSI
7210 drive system. Now that they do, they use their own moon tracking
software loaded onto a PC that commands the Vertex.

Late last month, the fruits of their efforts were demonstrated by
bouncing 20 radio signals off the moon. The dish sits on a 160-acre
site that’s been subdivided for residential sale, so the restorers
feel some urgency in trying to preserve it. Ideally, they’d like to
see it returned to service, perhaps to support scientific and deep
space missions. But they also think of it as an ideal location for a
space camp for star-struck students. Images are available at

“The Jamesburg Earth Station is in Cachagua Valley, California (about
20 miles S.E of Monterey).

This facility went into service in 1969, just in time to carry the
Moon landing live to the world. COMSAT owned and operated this high-
capacity earth station, and provided all forms of overseas
communications via satellite between the U.S. and points all around
the Pacific Rim. This antenna, taller than a 10-story building, is
located in the Upper Carmel Valley.

This facility was closed in 2002, and sold to a private investor. The
new owner is cooperating with a group of Ham Radio operators to find a
new use for the antenna, which may include  Radio Astronomy,
educational or Deep Space applications.”

For additional information, please contact Pat Barthelow at
aa6eg [at] hotmail [dot] com

Technical Information


This 30-Meter antenna and facility is located in Jamesburg,
California, 6 miles south of Carmel Valley village in a quiet radio

Lat: 36 24 11.1
Lon: 121 38 49.3
Horizon: ranges from 5 to 9 degrees.


Reflector Size: 29.7 meters (97 feet)
Surface: solid aluminum, with 0.01 inch accuracy
Gain: L band 47dB, C band: 56dB
Feed: Cassegrain with 3-7GHz feed horn. RHCP & LHCP are available.
Optional L band feed horn.
Additional feeds may be accommodated.

Positioning Control:

Vertex-RSI 7210, installed in 1999.  External PC interface for user
defined control.

Accuracy: 18 bit readouts on azimuth & elevation. 0.01 degree
resolution with 18bit optical encoders.

Tracking speeds up to one degree per second.

Drives are dual “opposing” 20 HP computer controlled DC synchro-motors
on each axis.

Backups drives for emergency steering if required.

RF Equipment:
3-7GHz LNA’s & down conversion to 1GHz
Rack, power and floor space are available to accommodate special


Large 20x20x15 enclosed feed room. Easy access to feed horn from
inside the feed room. Elevator and stair access.

Large 50x20x8 elevated equipment room adjacent to feed room
Large 40x50x15 Control Room connected to the tower base.
Secure 21,000 square foot solid concrete facility connected to the
Control Room.
Large bandwidth fiber links are installed and currently available.

This building contains offices, bedrooms, kitchen/dining area,
washrooms with showers, gym, indoor basketball court, large area rooms
for labs & equipment.

There is a multi-gated driveway & gated perimeter fencing around main
building & dish.

Security camera system blankets facility and is accessible through
internet connection for remote viewing.

Water well is on premises with two 15K gallon steel storage tanks.
Self contained fire suppression system for entire facility.
Dual redundant 40 ton HVAC systems.
12K volt 480/3 phase sub station on premise.
Entire Facility has redundant power capability.

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