October 1970 Popular Electronics
Table of Contents
Wax nostalgic about and learn from the history of early electronics. See articles
from
Popular Electronics,
published October 1954 - April 1985. All copyrights are hereby acknowledged.
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Popular Electronics
magazine
ran a monthly news roundup feature titled, simply, "Communications." Included were
tidbits on CB, SWL, HAM, RTTY, FAX, TV, SSB, AM, FM, CW, and ISB. I know that because
those are the acronyms in the string along the perimeter of the page's title. This
particular column was chosen because of the weird-looking Elser-Mathes Cup that
will commemorate the 1st amateur radio 2-way communications between Earth and Mars."
I thought it was an artifact of some primitive tribe's religious rite, but in fact
those are Martians in the carving, not Earthly savages. The inscription reads, not
surprisingly "First Amateur Radio Two-Way Communications Earth and Mars." No one
has been able to claim the trophy yet, but rumor has it
Elon Musk might do so before he dies. BTW, ISB stands for Independent SideBand.
Communications
Shortwave Listening
Broadcasters Change Frequencies - The majority of the international broadcasting
stations shift to winter/summer frequencies and schedules on November 1. Broadcasters
make four primary schedule changes each year (March, May, September, and November).
In view of the now rapidly declining sunspot cycle, shortwave listeners may expect
to hear more crowding on the lower frequencies - particularly 31, 25, and 19 meters,
Many of the broadcasters have abandoned 11 meters and a drastic curtailment of broadcasting
on 13 meters is expected in 1971.
Amateur Radio
Elser-Mathes Cup that will commemorate the "First Amateur
Radio Two-Way Communications Earth and Mars."
Planet Mars QSO - Visitors to the headquarters of the American Radio Relay League,
Inc. Newington, Conn., continue to be intrigued by one of the most unusual trophies
offered to ham radio operators, It is the Elser-Mathes Cup that will commemorate
the "First Amateur Radio Two-Way Communications Earth and Mars." Donated by Colonel
Fred Elser, W6FB/W7OX and. Lt. Cmdr. Stanley Mathes, K1CY (deceased), the cup also
honors Hiram Percy Maxim (founder of the ARRL), who had an intense interest in communicating
with Mars and Venus. When donated to the ARRL in 1929, the idea of ham radio reaching
even the moon was considered impractical, but ham-style E-M-E (earth-moon-earth)
reflected communications are now almost commonplace. Maybe the first man on Mars
will be a ham. If so, his trophy is all ready and waiting for him.
Broadcast Band
TV Antenna for DX'ing - If you have a selective receiver and would like to try
your hand at BCB DX'ing don't put up a long-wire antenna - you probably have a better
antenna right at your fingertips. Don't laugh, but it's your outdoor TV antenna!
Look at it this way: if you twist the two wires from the 300-ohm twinlead together
and connect them to your receiver ANT input, you have a top-loaded vertical - just
like a BCB transmitter. Make sure that the receiver GND goes to a very good earthy
ground because at the medium wavelengths that part of the antenna system is particularly
important. (Submitted by Frank H. Tooker)
Research
A Reading from on High - The FCC has been requested by Readex Electronics, Inc.
to establish a wholly new radio service called "Industrial Telemetry." Readex wants
assignments in the 216-220-MHz band for miniature low-power transmitters, plus frequencies
for a 5-watt command unit. The miniature transmitters would be installed by utility
companies and connected to water, electric and gas meters. Information on customer
usage would be put in digital code and the miniature transmitters interrogated by
a command unit in a high-flying plane! Readex says that an area of tell thousand
square miles can be covered in one flight and the readings would be recorded on
tape. Big Brother and 1984 are getting closer!
Amateur Radio
Novice or Technician Exams - Would-be hams in the state of Washington may take
their Novice or Technician class exams at one of the following locations: Amateur
Radio Supply Co., 6213 13th Ave. South, Seattle; G&C Electronics, 2502 Jefferson
St., Tacoma; and HCJ Electronics, 8214 Sprague Ave., Spokane. R. E. Aspinwall, W7PV,
says exams are year-round.
Citizens Radio (CB)
Channel 11-Now that the matter of channel 9 (exclusively for emergency traffic)
has been settled, REACT National Headquarters bas proposed voluntary nationwide
adoption of channel 11 for inter-licensee calling. Emphasizing that channel 9 had
originally been used for intra-station and inter-station calling, a new, nationally
recognized "calling" frequency must be sought.
REACT says that channel 11 appears to be an agreeable choice to most clubs, REACT
teams, and CB magazines, Popular Electronics agrees also.
Due to lack of space, we omitted Keith Glover's picture from
last month's interview with Richard Wood. Still looks good, though, so here it is
now.
Shortwave Listening
Clarification-Radio Nederland' s Tom Meyer bas corrected some misinformation
that appeared in Hank Bennett's June 1970 SWL column. First, tape recordings to
Radio Nederland for verification need not be Only 7 1/2 in./s; but may be any speed,
any track arrangement, and even in cassettes. Also, Tom's show is not a listener's
request program, although he is filing away his regular listeners' preferences (and
birthdays)., Musical requests are handled by Jerry and Dody Cowan's "His and Hers"
on Tuesdays and "By Request" on Mondays and Fridays.
Shortwave Listening
Jamming It Up - The Sino-Soviet communist block countries are gradually intensifying
jamming of international shortwave broadcasts. Practically all broadcasts beamed
to the Soviet Union and mainland China are being jammed. On August 1, a sweep across
the 19-meter band showed jamming on the following frequencies (practically a new
high) : 15,105; 15,115; 15,125; 15,130; 15,145; 15,170; 15,205; 15,215; 15,225;
15,260; 15,280; 15,290; 15,300; 15,340; 15,370; 15,380; 15,390; 15,440; and 15,445
MHz. Because of the splatter, this means that about 25 percent of the possible broadcasting
frequencies are useless.
Shortwave Listening
Chicom 1 - Space scientists are still perplexed by the telemetry from mainland
China's 380-lb satellite Chicom 1. Some specialists claim that it wasn't telemetry
at all - simply the tag end of a tape recording made to sound like something important.
Thousands of SWL's heard Chicom 1 on 20.009 MHz during its short life - an indication
that battery power was used in this 5-plus-watt transmitter. Tape recordings mailed
by SWL's to Peking have not been acknowledged - according to the latest information
- much less "verified." Experts are now partially convinced that the 20.009-MHz
frequency was chosen not out of respect for the ITU, but as a convenience since
Peking monitors the Soviet Cosmos series on 19.995 and 20.005 MHz.
Broadcast Band
Mexican Stereo - Where there's a will, there's a way; and since AM broadcast-band
listeners want stereo they can get it from XETRA, Tijuana, Mexico. Stereo enthusiasts
are advised to get a second AM receiver and tune one receiver to the lower sideband
of the 690-kHz AM signal and the other receiver to the upper sideband. Reports from
southern California about the quality and stereo effects are mixed, but at least
it's there for the tuning. (Submitted by Larry Sharp)
Citizens Radio (CB)
Unique Noise Silencer - Introduction of the "Noise Eliminator" Model CE-0-05
by Omega-t Systems Inc., opens exciting new possibilities in mobile operation. Intended
to supplement the built-in CB transceiver noise limiter, the Omega-t solid-state
(18 transistors, 1 IC and 11 diodes) device enables 100% copy of weak signals even
in the midst of a traffic jam. Besides eliminating noise, the unit also acts as
an r-f preselector. Basic operation (patent pending) is to take incoming signal
and compare it with noise on a nearby frequency. It then makes pulses from the noise
bursts and, when pulses exceed a preset level (adjustable by operator), shifts the
received frequency, which effectively switches off the preselect or and quiets the
transceiver. Only three connections are necessary to use the unit: antenna in, antenna
out, and 12-volt dc power.
Shortwave Listening
They Can't Do That To Us - Canadian shortwave listeners, police and fire signal
buffs, feel that their Department of Communications has "flipped." In an apparent,
but ill-advised, effort to stop unrestricted listening to police radio signals,
the DOC has issued a new ruling that requires an SWL to have a "Private Commercial
Receiving" license in order to listen to anything above 138 MHz. And, to add insult
to injury, the SWL must also have permission from the stations he wants to hear
in order to be granted the special license. According to reports in the Canadian
magazine Electron, Department of Communications inspectors are not paying a great
deal of attention to this new rule.
Research
Death of a Radar Echo - Try, try again, scientists are working on a "different"
approach to the absorption of UHF radar signals. Laboratory tests indicate that
a ballistic missile with recessed resonant antennas beneath an aerodynamically true
- but transparent skin - will absorb UHF energy. If enough is absorbed, the echo
return can be weakened to a point where detection at great distances is impossible.
Stumbling blocks to implementing this idea concern not only mechanics of preparing
missile skin, but determining Sino-Soviet radar frequencies.
Shortwave Listening
Speech Scramblers - Next year we can celebrate the 70th anniversary of first
attempts at electronic speech scrambling - Alexander Graham Bell tried it, but the
results were unimpressive. Local and state police are increasingly concerned over
the influx of VHF /UHF monitoring receivers and speech scrambling is being installed
in an average of three police communications systems per month. The E. F. Johnson
Co. has demonstrated a hand-held VHF transceiver with 6 possible modes of scrambling.
It will sell for about $1000 per unit - not considered too high for the extra security.
Scrambling can be speech inversion, band splitting, frequency modulation, analog,
or time division. Band splitting was used during World War II for supposedly secure
messages between Roosevelt and Churchill, but the Nazis managed to unscramble it.
Citizens Radio (CB)
Canadians Get CB Reciprocity - In a sudden unexpected move, the FCC on July 24,
granted CB reciprocal operating privileges to all Canadians coming into the U.S.
with bona fide GRS licenses. CB'ers from the States have been able to operate in
Canada for several years and a reciprocal arrangement had been advocated by numerous
CB organizations. Canadians must request permission using FCC Form 410 (New Form
410-B after November 1) and should understand the FCC Part 95 CB Rules and Regulations.
While in the States, Canadians use their "XM" callsigns followed by a geographical
identification (city and state).
Posted January 29, 2024 (updated from original post on 9/19/2017)
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