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June 1969 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 June 1969 issue of
Radio-Electronics magazine features the following news items. University of
Wisconsin engineers tested cryogenic "neuristors" in liquid helium, mimicking
brain neurons for ultra-dense computing. Bell Labs developed a 600-component IC
for Picturephone timing circuits. A revised maritime signal code added medical
terms like "Oo-nah-won" (broken thumb). A study found 20% of U.S. color TVs leaked dangerous X-rays due to high voltage. Japanese firms Matsushita and Mitsubishi demonstrated early flat-screen TVs, while U.S. research shifted to plasma displays. NASA and India planned satellite TV for remote villages, hinting at future U.S. educational broadcasts. FM radio, once written off, reached a milestone
- 50% of 1968 radios sold included FM tuners. New & Timely
Cryogenic neuristor in its liquid helium bath is studied at U
of W.
Neuristor "Gray Matter" Ahead?
Cryogenic neuristor in its liquid helium bath is studied at
U of W.
Madison, Wis. -A super-dense electronic brain using cryogenic tunnel junction
neuristors is feasible according to three University of Wisconsin electrical engineers
now investigating "synthetic gray matter."
In liquid helium, neuristors work similarly to the 10 billion neurons of the
human brain. Insulating material sandwiched between two strips of superconducting
metals breaks down when a pulse is applied across one end of the strip. The pulse
travels to the opposite end much like a nerve impulse.
With IC techniques, component densities of 200 million per square foot are economically
possible, the engineers believe. Since neuristors draw no current in the resting
state, a brain-size system would not require excessive power.
Profs. A.C. Scott, R.D. Parmentier and J.E. Nordman feel the nearly impossible
task of connecting individual neuristors could be overcome by "teaching" neuristors
into a pattern, imitating the brain's organization of its neurons.
This might be done by adding bits of ferromagnetic material between each neuristor.
When information is programmed in, the bits would become increasingly magnetized,
gradually establishing preferential neuristor current paths.
 600-Component
IC Controls TV Phone
Murray Hill, N.J. - Through its close-up lens this Picturephone displays one
of the key IC's that controls its timing circuits. The Bell Labs-produced IC has
some 600 components in less than a square inch. It controls the TV telephone's
CRT scan rate, frames per second and interlacing-to sharpen the picture and
eliminate flickering. The Picturephone, currently being trial-tested be-tween
the New York City and Pittsburgh offices of Westinghouse Electric Corp., is
expected to be put into nationwide service within a few years.
Revised Signal Code Has Medical Symbols
"Oo-nah-won, ok-to-ait" might mean a broken thumb at sea. This code word
pronunciation for the number 18, code for a thumb, is part of a revised International
Code of Signals that went into effect April 1.
The new code contains a detailed list of diseases and parts of the body by number,
and is meant to improve medical communications over marine radiotelephones.
Alfa, Bravo, Charlie, Delta alphabet designations that replaced the Able, Baker,
Charlie, Dog code in the 1950's have been retained in the code revisions. But the
syllables that should be stressed have been emphasized. In "November," the code
word for "N," the "vem" should be stressed, for example.
 TV X-Rays Are Back
Suffolk County (Long Island), New York - A 14-month study of 5000 color sets
conducted by the Suffolk County Health Department indicates that 20% of the sets
were delivering excessive x-rays.
The study covered sets from 37 manufacturers, and at least one color receiver
of each brand was found to be emitting radiation in excess of the danger level (0.5
milli-roentgens an hour at a distance of two inches from the surface of the set).
The door-to-door survey was conducted by Seymour Becker, a physicist with the
County Public Health Service.
Using these figures in an extrapolation, three million of the 15-million color
sets now in use in the United States are emitting excessive x-rays.
Mr. Becker reports he found 15 separate causes for the excessive radiation, which
was being emitted in all directions. Mr. Becker said that all x-ray emissions, even
non-harmful ones "technically can be reduced to zero."
The amounts of radiation measured varied from 0.5 mR at 5 cm to as much as 150
mR. The average offender emitted 2 to 5 mR.
Power supply voltages in the malfunctioning sets ran as high as 40,000 volts
with an average of 32,000 to 38,000. Normal high voltage is about 25,000 volts.
Editors Note: An excessive high voltage is almost always accompanied
by x-ray emission we recommend all technicians to check the high voltage of every
color set they service and make any needed repairs. To the set owner we urge that
you look at your picture carefully. If it is out of focus or narrow (black edges
at the right and left) have your set's high voltage checked immediately. The troubles
just described are often produced by excessive high voltage. And excessive high
voltage is often accompanied by excessive x-rays.
Looking Ahead
By David Lachenbruch, Contributing Editor
Flat Screen Breakthrough?
Although many American companies in the last 20 years have claimed progress toward
an electroluminescent picture-on-the-wall flat TV display, none is believed to have
progressed to the point where an actual off-the-air television picture could be
shown. Now, at almost exactly the same time, two Japanese firms have actually shown
recognizable pictures on experimental display panels. Both Matsushita Corp. (parent
company of Panasonic) and Mitsubishi Corp., developers of these flat-screen approaches,
say their use for television is still some time off.
In the U.S., attention appears to be shifting from electroluminescent panels
to plasma devices in research looking toward elimination of the picture tube. Several
projects are under way to develop color displays utilizing trapped ionized gases
which glow in different colors.
Off-Color Commercials
The continuing television industry study of the lack of color uniformity in broadcast
transmissions (Looking Ahead, April 1969) has come up with an interesting reason
why commercials often show up poorly on color TV: It's not your set or the transmitter;
nearly 40% of filmed commercials may have bad color in the first place. In subjective
and objective evaluations of a large number of films shown on television, an engineering
task force found that 35mm films had less color variations than 16mm, and that program
and news films varied less than commercials.
Then 180 commercials were tested, and the task force concluded that "30 would
not look good to any observer on TV or direct projection," while another 40 were
rated "questionable."
Pictures from Space
A space broadcasting experiment in India may eventually bring a new kind of television
service to the United States. NASA and the Indian Government are planning to test
a low-cost method of mass education by satellite TV in 1972. Some 80% of India's
population lives in 568,000 villages. The goal of the joint space venture is to
reach these villages with educational telecasts from space.
Each community TV receiver, which can be watched by as many as 300 people at
a time, will have its special 5-foot parabolic antenna and FM-to-AM converter to
translate direct satellite signals into a standard TV set waveform.
Although direct satellite-to-home TV broadcasting won't be economically feasible
before the 1980's at the earliest, NASA officials think the Indian project could
lead to new TV services in the U.S. Low-cost ground stations could supplement regular
TV service by filling in isolated areas which currently aren't covered by television
stations. Another system could cover the U.S. with non-entertainment programing
for specialized groups. For example, special programs for doctors, lawyers or scholars
in certain fields - prohibitive in cost if beamed from a network of ground transmitters
- could be transmitted from a single satellite, picked up by mass-produced ground
stations and distributed to offices or homes by existing cable TV systems, or piped
directly to receivers in colleges or assembly halls.
FM's Landmark
If you're old enough, you'll remember that FM radio was once given up for dead
- but it refused to be buried. Well, FM reached a happy milestone in 1968. After
all sales figures had been tallied, it turned out that exactly 50% of all radios
sold last year contained FM. Americans bought 36 million table, clock, portable,
auto and phono and/or TV combination radios-and 18 million of them had FM. A lively
corpse, indeed.
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