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October 1960 Radio-Electronics
 [Table of Contents]
Wax nostalgic about and learn from the history of early electronics.
See articles from Radio-Electronics,
published 1930-1988. All copyrights hereby acknowledged.
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The
Echo 1 communications satellite was launched in August of 1960, shortly
before this October 1960 Radio-Electronics magazine "News Briefs" item
reported on the preparations made for the first message to be bounded off the
metallic film covering its spherical shape. The November 1960 issue of
Electronics World magazine included an infomercial from Bell Telephone
Laboratories claiming success. While waiting for Echo 1 to be placed into orbit,
tests were made of the round-trip signaling system by bouncing signals off the
moon. The moon, being about a quarter million miles farther away from Echo's
orbit and having a much less radio-reflective surface than Echo, resulted in a
significantly weaker received signal. That confirmed the system would perform
well with the Echo 1 signal. In fact, as mentioned above, everything went
exceptionally well.
New Briefs:
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News Briefs
Space-relay terminal at Holmdel, N.J. Transmitting antenna is at left, the receiving
horn at the right of the photo. Receiving equipment is in shack at horn's end.
Echo Satellite Opens Way to New Communications System
The successful transcontinental telephone conversations via the Echo satellite
may be only the beginning of a complete system of telephone and TV relay communications
via satellites. This is the opinion of scientists both of the National Aeronautics
and Space Administration (NASA) and of the Bell Telephone Laboratories, who collaborated
to put Echo into space.
The first satellite is a sphere 100 feet in diameter, making a circuit around
the earth in a little over 2 hours, and traveling roughly 1,000 miles above the
earth on a course angled 47° from the equator. Two tiny transmitters 180°
apart on the sphere's equator help the ground stations to track it. Otherwise Echo
is a complete passive reflector.
A number of satellites, either three or four at great heights, as proposed by
Hugo Gernsback in Radio-Electronics, March, 1958, or a system of 50 traveling at
about the same height as Echo, could carry a fantastic number of messages and provide
reliable communication at all hours of the day.
As a rehearsal for Echo, phone messages were exchanged between Holmdel, N. J.,
and Goldstone, Calif., using the moon for a reflector. Reception, as witnessed by
a large group of reporters, was completely intelligible, though much more noisy
than the later Echo transmissions. The same receiving equipment was used later to
track and receive Echo.
In transmissions between the Bell station at Holmdel and Jet Propulsion Laboratories
at Goldstone, power in the order of 10 kw for the transmitters was used at both
ends, the West Coast station operating at 2390 mc and the Bell Labs transmitter
at Holmdel using 960 mc. The receiver is a ruby maser type, which, in conjunction
with the special horn antenna, reduces noise to a negligible level.
 Hams Bounce Signals off Moon
The first amateur radio moon-bounce contact was made July 21 between the Eimac
Radio Club in San Carlos, Calif., and Sam Harris of the Rhododendron Swamp VHF Society,
Medfield, Mass. The frequency used was 1,296 mc. At both ends of the circuit, a
1,000-watt (maximum allowable power) klystron was used in the transmitter and a
sensitive Microwave Associates MA2-1000 parametric amplifier in the receiver.
The contact took place between 7:30 and 8:00 am, PDT.
The photograph shows some of the members of the Eimac Radio Club who participated
in the moon-bounce project. They are, left to right, standing: W6OUV, Robert Sutherland;
W6HB, O. H. Brown; W6UF, Bill Eitel; W6RXW, George Badger; W6MUC, Al Clark; K6GJF,
BQb Morwood ; sitting, W6KEV, Ray Rinaudo ; W6IVZ, Charles Anderson and K6GSO, Allan
Beer. Not shown are Bill Orr, W6SAI, and Mike Krivohlavak, K6AXN.
Underground Radio
A teletyped radio message has been sent through 4 1/2 miles of the earth's substrata
by Developmental Engineering Corp. The message was sent on a frequency of 150 kc,
but anything between 30 kc to 3 megacycles is suitable.
The transmitter was placed 1,000 feet below the surface in a mine near Carlsbad,
N. M. The receiving equipment was in a second mine 4 1/2 miles away.
The Lithocom system is not suitable for general broadcasting as the signals do
not go above ground. The main value of the system lies in the fact that it is very
difficult to jam. It can be used as an emergency means of communications. In a war,
the enemy could not listen in (the expected maximum range is 100 miles).
Reflecting Ring to Orbit Earth?
A plan to ring the earth with billions of tiny antennas is to be tested by the
Air Force. Each antenna will be about half as thick as a human hair. Their length
will depend on the frequencies to be used.
The ring will be used to relay signals from point to point by reflecting them
off the ring in a manner similar to bouncing signals off the Project Echo balloon.
It is planned to place a small number of antennas in orbit by a vehicle with
a different main mission. The vehicle may be launched within a month or two.
One objection to the plan is that the ring might block signals used in other
space projects.
The ring would not be as likely to be damaged by meteorites or space debris as
would balloons or "active" (receiver-amplifier) satellites.
FM Increasing
FM stations are developing faster than AM stations, according to the latest count.
Of course, AM stations still outnumber the FM's (3,484 AM's, 741 FM's), but percentage-wise,
FM is ahead,
From 1958 to 1959, the number of operating FM stations increased from 571 to
677 (19% based on 1958 figures), while in the same period AM stations increased
from 3,318 to 3,456 (4%).
In the period from Jan, 1 to June 30 of this year, 64 new FM stations went on
the air (an increase of approximately 10% in just half a year), while 28 AM stations
went on the air (approximately 1% in half a year).
Party Lines Next?
Two widely separated computers can now exchange information with each other over
a telephone system at the rate of 150 characters or numbers per second, the International
Business Machines Corp. reported recently. The system requires a pair of IBM 1009
data-transmission units, one at each end of the line.
Information from a core storage unit, punched cards or magnetic tape may be sent.
Posted July 16, 2024
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