October 1960 Electronics World
Table of Contents
Wax nostalgic about and learn from the history of early electronics. See articles
Electronics World, published May 1959
- December 1971. All copyrights hereby acknowledged.
We recently passed
the 62nd anniversary of the first successful earth-moon-earth (EME) communication
path by amateur radio operators. What is today a routine operation by Hams was a
big deal back in the day. The moon was still a mystery to most of the world since
at the time not even an unmanned probe had been sent for exploration. As
reported in this 1960 issue of Electronics World magazine, 1,296 MHz
was the frequency of choice using a 1 kW klystron on the transmit end and a
highly sensitive parametric amplifier on the receive end, with high gain parabolic
antennas on both ends. The Federal Communications Commission
(FCC) has allocated the 144.00-144.20 MHz
(2 m), 222.0-222.025 MHz
(1.25 m), 432.00-432.07 MHz and
(70 cm), 902.8-903.0 MHz
(33 cm), 1295.8-1296.05 MHz
(23 cm), and 2303.9-2304.2 MHz bands for
various modes of EME operation per Part 97 rules.
Ham Radio Earth-Moon-Earth Contact
Some members of the Eimac Radio Club in San Carlos, California,
who participated in the moon-bounce circuit are shown here with their make-shift
Details on the first amateur radio moon-bounce two-way microwave contact between
California and Massachusetts.
The first amateur radio moon-bounce two-way microwave communication took place
on Sunday, July 17 between two distant points. This contact marks an important milestone
in the development of amateur radio. The historic contact was between the members
of the Eimac Radio Club in San Carlos, California and Mr. Sam Harris, Rhododendron
Swamp VHF Society in Medfield, Mass.
After months of personal effort by the radio amateurs concerned with this project,
signals were transmitted in both directions on 1296 mc. The equipment was then refined
and the first successful two-way communication was made. The first transmission
was from West (W6HB) to East (W1BU). The pattern was then reversed and the first
amateur coast-to-coast communication via the moon completed. At each end of the
circuit, a 1000-watt klystron was used in the transmitter and a very sensitive parametric
amplifier in the receiver.
Path of the 1296-mc. microwave signals.
This successful reception and transmission using the moon as a signal reflector
will stimulate efforts to improve amateur-built equipment for further moon-bounce
communications. The only other moon-bounce communications equipment in existence
is military or experimental in nature; the principal installation is the Naval link
between Washington and Hawaii.
Members of the Eimac Radio Club who participated in the moon-bounce circuit are:
Bill Orr, W6SAI; Hank Brown, W6HB; Bill Eitel, W6UF; Ray Rinaudo, W6KEV; Bob Morwood,
K6GJF; Bob Sutherland, W6UOV; Hugh MacDonald, W6CDT; George Badger, W6RXW; Allan
Beer, K6GSO; Al Clark, W6MUC; Mike Krivohlavek, K6AXN, and Charlie Anderson, W6IVZ.
Posted December 2, 2022
(updated from original
post on 7/9/2014)