Billed at the time as the longest
microwave relay system in the world, this report on Bell Telephone Systems' transcontinental
installation came just a month after being put into commercial service. At a cost
of $40 million ($650 million in 2015 dollars per
BLS Inflation Calculator), the system relays telephone calls and
radio and video program material along a chain of 107 microwave towers, spaced approximately
30 miles apart. It was a big deal to be able to watch a TV show from New York City
in Los Angeles, and vice versa; we take worldwide broadcasts for granted nowadays.
Bell System Opens Transcontinental Radio-Relay
By William Alberts
Original commercial service provides two TV channels - one east and one west.
Other channels will be added as needed.
Air view of Long Lines radio-relay station at Mt. Rose, Nevada.
At an elevation of 10,000 ft., this is highest station in system.
By the time this issue reaches our readers coast-to-coast commercial television
will be a reality. This video link has been made possible by the completion of the
new microwave radio-relay built by the Long Lines Department of the American Telephone &;
Radio-relay station at Creston, Wyoming, showing both the receiving
and sending microwave antennas at two different levels.
This new project is the longest microwave system in the world and is the product
of years of engineering effort and cooperation by the development, manufacturing,
and operating units of the Bell System.
The relay was put into temporary service on September 4th to carry the ceremonies
in connection with the Japanese Peace Treaty Conference held in San Francisco. Built
in about three years at a cost of $40,000,000, the system relays telephone calls
and radio and video program material along a chain of 107 microwave towers, spaced
approximately 30 miles apart.
The vast distances, together with the large number of radio channels required,
posed many serious problems for the Bell Telephone Laboratories. Three new developments
provided the answers. First, a new electronic tube was developed which gave outstanding
performance at the super high frequencies. Second, the Laboratories came up with
a new improved metal lens which would handle thousands of simultaneous telephone
calls. A unique system of filters, representing an entirely new contribution to
the field of communications, was developed. All of this electronic equipment was
built and installed by the Western Electric Company, the manufacturing unit of the
Cutaway view of a typical concrete station in Long Lines transcontinental
radio-relay system just put into service.
Operating in the 4000 mc. range, the new relay system employs amplifying equipment
at each station to boost the signal 10,000,000 times before retransmitting.
Initially, the system will provide one east-to-west channel for television. The
west-to-east channel is expected to be in service within a few weeks.
One of the concrete stations on the radio-relay route between
Chicago and Des Moines.
The story of how this vast system came into being is one worthy of the days of
pioneering. In locating and constructing the 107 towers comprising the system, the
engineers encountered every type of terrain. The first step in determining a tower
site involved the study of topographical maps and then an on-the-spot inspection
to determine clear paths between prospective stations and the detection of all reflective
surfaces, such as water or flat lands, that might impair the signal. To insure best
construction conditions and ease of maintenance, the accessibility of the site to
all-weather roads had to be considered.
Next, sites about 25 miles apart were tentatively selected with alternate sites
chosen in each instance. The land for each station was then optioned and field tests
were held to determine the transmission and reception quality of that particular
Following the preliminary tests, borings were made and soil samples taken to
determine the type and depth of foundation necessary for each station. In addition
to securing the necessary FCC authorization, clearance had to be obtained from the
CAA because of the towers and their rulings heeded as to outside lighting for the
The 200 foot steel tower at Salt Lake City Junction overlooking
Salt Lake City and Great Salt Lake. This is one of the 107 stations on the transcontinental
Depending on the location of the stations, the towers range in height from 40
to 200 feet. In many cases they are concrete buildings with space on the ground
floor for a gasoline engine to generate emergency power in case of power line failure.
The second and third floors of the stations house the storage batteries and associated
power equipment. The amplifying and testing gear is housed on the fourth floor while
the top of each station carries the horn-shaped directional antennas.
Unusual view of the Cisco-Butte, California station of the transcontinental
relay system. This station is located in a valley high in the Sierra-Nevada mountain
All-in-all this vast engineering feat represents an important addition to the
country's communications facilities for both peace and war, provides coast-to-coast
network facilities for the transmission of television programs, and opens up thousands
of new channels for long distance phone service.
With the completion of this new microwave relay system the country now has seven
telephone highways crossing the continent.
90-Mile Laboratory for Telephone and Television,
6/1945 Radio News
Wire-Wrap, 10/53 Radio-Electronics
EDT Crystals, 10/47 Radio-Craft
Refining, 5/54 Radio & TV News
Timekeeping, 1/46 Radio News
Transatlantic Cable, 11/56 Radio & Television News
Pipe Circuits, 11/48 Radio & Television News
Coaxial Electron Tube, 6/54 Radio & Television News
Wire Bonding, 3/58 Radio News
Radio Relay Stations, 8/52 Radio & Television News
Isolators, 6/56 Radio & Television News
Punch Cards, 3/55 Radio & Television News
Over-the-Horizon Communications, 10/55 Radio & Television News
Memory Devices, 2/58 Radio & TV News
Adventure in Silicon, 5/55 Radio & Television News
of Progress, 6/55 Radio & Television News
Project Echo, 11/60 Electronics World
Diode Speeds Voices, 8/58 Popular Electronics
Antenna, 5/46 Radio-Craft
- Quality Control,
6/46 Radio News Article
Transcontinental Radio-Relay, 10/51 Radio & TV News
Solar Battery, 7/54 Radio & Television News
Germanium Transistors, 1/54 Radio & Television News
Cavity Magnetron, 10/45 Radio News
The Cableman, 10/49 Radio & Television News
Coaxial Cable, 12/49 Radio & Television News
Tin Whiskers, 12/55 Radio & Television News
Relay Contact Inspection, 7/55 Radio & Television News
Transistor's 10th Anniversary, 6/58 Radio & Television News
Wire Wrapping, 10/53 Radio & Television News
Junction Diode Amplifier, 11/58 Radio News
Nobel Prize Winners, 2/57 Radio & Television News
Diode Speeds Voices, 8/58 Popular Electronics
Microwave Relays, 7/59 Electronics World
Posted December 24, 2015