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September 1961 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 "News Briefs" column in a 1961 issue
of Radio-Electronics magazine included an item which might cause modern
day feminists to develop a case of
the vapors. Miss
Marlene Schmidt, of
Stuttgart, Germany, was crowned with the title of Miss Universe 1961. The rub:
She had already earned a Master's degree in engineering, and was
working in research for an electronics and radio company. Also, in the news
was a new "ultraminiature" transistor from RCA, and Canada was on the verge of
commissioning is first stereo FM radio stations. Speaking of FM, the FCC in
the U.S. proposed new rules on the physical distance between FM broadcast towers
based on their power output.
New Briefs:
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News Briefs
 Electronics Engineer Becomes Miss Universe
The 1961 Miss Universe is an electronics engineer who expects to return to the
job as soon as her tour as Miss Universe is completed.
Marlene Schmidt of Stuttgart, Germany, is electronics' answer to Marilyn Monroe.
She was crowned this summer at Miami, Fla., in competition with beauties from all
parts of the world. A year of travel and guest appearances is one of the prizes.
"But when the year is over, I will return to the job," says Miss Schmidt, who has
been given a leave of absence by her employer. "Engineering is my career. I've been
interested in technical subjects since I was 5." Anyone for engineering?
 Ultraminiature Transistors
Thin-film transistors are so small that up to 20,000 of them can fit on a postage
stamp. This new device, which comes from RCA's David Sarnoff Research Center, is
made by depositing thin films of semiconductor materials on an insulating base.
Each finished device is only a few ten-thousandths of an inch thick. Using such
transistors, it will be possible to shrink the basic circuitry of a computer to
the size of a book page.
The active material used in the semiconductors is cadmium sulfide. In making
thin-film transistors, an evaporation process is used to deposit successive thin
layers of cadmium sulfide and metal on a glass plate. In the evaporation process,
the cadmium sulfide crystals and the metal are heated in successive steps in a vacuum,
turning to vapor that is collected by condensation on a glass plate. By using a
special mask to cover portions of the plate during the process, the metal layers
are deposited in a pattern that forms the electrical contacts needed to operate
the transistor. The masking process can also be used to produce various patterns
of connections among many transistors to complete a desired circuit at the same
time the transistors are being made.
The completed transistor is not only very tiny, but also incorporates an important
operating feature not now used in commercial transistors. In conventional transistors
having comparable functions, electrons flow more or less freely through the semiconductor
material between two of the contacts, and the third element provides control by
reducing the flow in varying degrees. The operating principle of the experimental
thin-film units is exactly the opposite. The insulating properties of the cadmium
sulfide hamper the flow of electrons between the two electrodes, and the third element
provides control by increasing the flow in varying degrees.
The photograph shows an enlarged laboratory test unit containing three thin-film
transistors made in special elongated form on a glass base.
Stereo FM for Canada?
The Canadian Radio Technical Planning Board, representing the Canadian radio
industry, has submitted proposals to the Department of Transport, Ottawa, for FM
multiplex stereo broadcasting. (Radio in Canada comes under the jurisdiction of
the Department of Transport.) The department is stated to be studying the matter,
and it is expected that stereo broadcasting will be permitted.
FCC Proposes FM Rule Changes
FM proposal recently issued by the FCC is aimed at simplifying station
allocations. It sets up definite spacings for FM stations, as is now done in TV,
and avoids the complex considerations used to calculate an AM transmitter's
service area. Three classes of commercial FM stations are proposed: class A,
with an effective radiated power of 1 kw and 250-foot mast (the formula permits
more power if the mast is lower or limits it for a higher mast) ; class B, 20 kw
and 500-foot tower; class C, 100 kw and 2,000-foot antenna (above average
terrain). Spacing of class-A stations would be 115 miles ; class-B, 190 miles;
class-C, 300 miles. Two classes of educational stations are proposed: class D,
10 watts and 100 feet; class E, same as for maximum commercial station at the
same location." Comments were asked on polarization of FM signals. The
commission noted the growing number of FM auto radios, whose vertical antennas
can receive a vertically polarized signal best. FM is now horizontally
polarized, though circular polarization is permitted. The question of
duplication of AM and FM programs was also raised, with comments invited "as to
whether complete or partial duplication should be allowed for any FM station.
 New
"Solid-State" IFT
A new type of ceramic coupling unit announced by the U. S. Sonics Corp. of
Cambridge, Mass., is expected to show some advantages over crystal and
magnetostrictive filters, especially in price. The new and very small device
consists of two discs of a modified zirconate compound, approximately 14- inch
in diameter. These are in contact, and the coupling between them is acoustic.
Input and output leads are to the outside centers of the two discs, and the
common lead to a point on the inside circumference of both. Two types were
reported available, both at 455 kc. The transistor type is rated at 10 kilohms
input, 1 kilohm output; the input impedance of the tube type is 25 kilohms and
the out¬put 200 kilohms. Insertion loss for both types is in the order of 1 db,
and the bandwidth at 3 db down is 6 kc for the transistor type, 2 kc for the
tube type.
Posted September 9, 2024
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