September 1947 Radio-Craft
[Table of Contents]
Wax nostalgic about and learn from the history of early electronics.
See articles from Radio-Craft,
published 1929 - 1953. All copyrights are hereby acknowledged.
The "Monthly Review" column
appearing in Radio-Craft magazine was an assorted collection of news tidbits
about electronics and communications industry happenings, similar to contemporary
magazines. Looking back to 1947, the world was hopeful about the future as World
War II was finally over and even the loser countries were focusing on how their
societies would be shaped by technology and lessons learned in the preceding seven
to ten years (depending on when a country entered the war). Two items here are particularly
interesting because they refer to ongoing research into large screen televisions
and video phones (aka "televisers"). Large screens at the time meant either much
bigger cathode ray tubes (CRTs) or projection systems - both of which came to fruition
in the 1960s and 1980s,
Plasma screens, then LCD and finally LED screens mark the eventual evolution. Holographic
displays as predicted in the 1970s have still not been realized. We have had video
phone capability for a decade and a half with the incarnation of camera-equipped
smartphones. Even so, there is not a whole lot of casual person-to-person televising
going on. Dick Tracy watches still are not the norm (even the
iWatch attempt is lame), which
we were pretty much promised to us by the year 2000.
Items Interesting to the Radio Technician
Mr. Sakharov using his telephone-televiser in the USSR Television
Televisors for Rent are being offered by a New York City service
concern. The rental cost is $2.50 per day, and a week's service is the minimum permitted.
Under the plan, television receivers are delivered, installed and picked up anywhere
in the metropolitan area.
Proximity Fuzes which were operated by light instead of radio
waves were used on rockets during the, war, it was disclosed last month by Frank
A. Zupa of Bell Telephone Laboratories. The "seeing-eye" fuze functioned when proximity
to the target cut off part of the light which normally reached it. Essential parts
of the device were a ring-shaped lens built into its nose, a photocell, an amplifier,
and a selective switch. When the rocket was fired, the selective switch armed the
fuze by throwing the amplifier into circuit.
While the rocket was in flight, daylight entering through the lens and striking
the photocell maintained a certain level of current that did not activate the detonating
mechanism. As the missile approached its target, however, some of the light was
cut off by the target itself, and the resulting change in current level served to
setoff the explosive charge.
Apparently this type of fuze was useful only during the day, and would not be
useful in conditions of twilight or darkness.
Pay-As-You-See television was pro-posed last month by Commander
E. F. McDonald, president of Zenith Radio Corp., as a means of solving the economic
problems of television broadcasting.
According to the plan proposed by McDonald, scrambled television signals would
be sent through the air to the receiver in the usual fashion. Special unscrambling
signals would be sent over the telephone wires, to which the set would be connected.
To receive the program in intelligible form, the user would call the telephone operator
and ask for "Phone-Vision." Payment for the television service could then be made
through the telephone company, much as for a long-distance call if arrangements
can be made with the 'phone companies.
The subscriber's telephone could be used for ordinary calls while receiving a
program, without interference either to the program or telephone conversation.
Commander McDonald states that experimental transmissions have already been made,
and that technically the system is quite successful. Telephone officials point out,
however, that there might be legal obstacles, at least in some states.
Citizen's Radio is about to come out of the blueprint stage,
a last month's Science Service report states. Fifty manufacturers and experimenters
are already talking on the allotted 460-470 megacycle band under experimental licenses.
About 500 small portables are already in use by police, firemen, foresters, geologists,
and motion picture producers.
Radio engineering advances made during the war are helping to speed the day when
such personal radio-telephone sets can be bought and when the FCC will allow them
to be used. Printed circuits, in which metallic paint on plastic or ceramic plates
replaces conventional soldered wires, will make the new sets lighter and smaller.
Miniature tubes, such as used in the famous wartime proximity fuzes, will in some
cases replace 3 or more tubes of conventional prewar radio sets.
Manufacturers' are not yet ready to guess at what these Citizen's Radio Service
sets will cost. Probably they will be in the price class with the better kind of
You can't yet apply for a license to operate a citizen's radio because the rules
and regulations are not yet drafted by the FCC. The new service probably will not
be legalized before early next year.
James G. Harboard president of the Radio Corporation of America
before 1930 and since that time chairman of the Board, retired under RCA's regular
pension plan on July 11. David Sarnoff was elected to serve in his place as chairman
of the Board as well as president of the corporation.
The retiring chairman also held the rank of lieutenant general in the United
States Army; which he entered as an enlisted man in 1889, rising to the rank of
major general during the first World War. His promotion to lieutenant general came
At the same time, Orrin E. Dunlap, Jr., was elected vice president in charge
of advertising and publicity. Mr. Dunlap has been with RCA since 1940, serving first
as manager of the Department of Information, then as director of advertising and
publicity. He was radio editor of the New York Times for 18 years, and is the author
of 10 books on radio, radio advertising, television, radar, and related subjects.
Radar terrain-clearance indicators will be required on all air
lines for a 2-year experimental period beginning January 1, 1948, the Civil Aeronautics
Board indicated last month.
Several devices are competing for the selection as approved equipment, among
them being the new Hughes lightweight clearance indicator, the light Army radar
described in Radio-Craft last March, and a similar radar developed jointly by the
Navy and American Airlines.
Advice to young scientists not to take too much for granted
because it is backed by authority was given by Dr. Harvey C. Rentschler on his retirement
as director of Westinghouse lamp and electronic tube research last month.
"The best research engineers I have known," he said, "have been those whose minds
are open to conviction and who are able to make their own decisions. Just because
something is stated as a fact in the scientific literature is no positive proof
that it is a truth. Formulas, equations and rules were made to be challenged and
exist only because someone challenged former rules.
Large-Screen television is about to make its commercial debut,
a last month's report issued jointly by RCA and Warner Brothers Pictures states.
The large-screen video will be introduced in a Broadway theater by Warners and
may also be piped into other theaters operated by the company. Preliminary tests
made by Warners and RCA indicate that spot news and special events coverage lend
themselves to theater presentation, and the television feature will be presented
in conjunction with other newsreel subjects.
Another large-screen commercial television installation is proposed at the Monte
Carlo Swimming Pool at Asbury Park, N. J. A screen 6 x 8 feet is to be used.
The screen is said to offer a new form of direct projection from the face of
the tube to a brighter-type screen. The life-size projection will give its audience
day and night baseball, boxing and wrestling, as well as any other important events
televised in course of the season.
Radio Items of the Month
Ultimate in radio service was offered recently by the Radio Center of Yonkers,
N. Y. An advertisement of that company carried the following:
To the Thieves Who Stole My 22 Radios
Remember, We Guarantee Our Radios Whether You Buy or Steal Them.
Facsimile transmission capable of sending a million words a minute was revealed
last month by Niles Trammel, president of NBC. The equipment, under development
by RCA, combines present facsimile and television techniques.
Deafness tester which uses a 2-toned whine to tire normal ears and temporarily
dull their receptivity was reported last month by Dr. Mark B. Gardiner of the Bell
Telephone Co. The test is designed to determine the type rather than the extent
Television equipment is being constructed to be used underwater at the site of
last year's Bikini atom-bomb explosion. It will be used in a scientific survey of
the results of the underwater bomb explosion.
Diathermy equipment which causes radio interference is no longer permitted to
operate in the United States. The owner of any such equipment must either modify
it to comply with FCC regulations or cease operating it altogether.
Television broadcasts now cover territory inhabited by 25,000,000 people.
Television which permits the parties in a telephone conversation
to see each other was reported from Russia last month. The face of the person at
either end of the line is shown on a small screen. The image is picked up by a lens
beside the video screen.
The device is the invention of I. P. Zakharov, a staff worker of the USSR Television
Research Institute. He calls his invention a videotelephone. A number of the devices
installed at the Institute are reported to be working satisfactorily.
If successful, the videotelephone will fill a long-felt need, as some of the
very earliest concepts of televisors were of instruments which would permit adding
vision to sound in ordinary telephone conversation.
Australian reception of American FM stations was not due to
improved or "new" receiving apparatus, as early newspaper reports implied.
Queried on the subject, Radio-Craft's Australian correspondent, John W. Straede,
states: "I spoke to Mr. Graham, who with his brother runs a radio shop in Melbourne.
He tells me the radio is a standard FM-AM receiver with nothing new or startling,
and that reception on the longer wavelength FM bands (30 to 40 mc) is fairly consistent
in the summer.
"The stations received are mostly police and emergency services such as fire
A Perfect Robot has been the dream of scientists throughout
the ages. This dream may be a little nearer to realization as a result of progress
with electronic "thinking machines." At least some of the men who helped design
and build these machines think so.
Says Professor Norbert Weiner of the Massachusetts Institute of Technology: "I
defy you to describe a capacity of the human brain which I cannot duplicate with
electronic devices." Professor Edwin G. Boring, director of Harvard's psychological
laboratory, is willing to go even further: "... it should require only a matter
of time, patience and continued support from some foundation," he says, "to design
a bright and attractive dinner companion or eventually even the perfect professor
Vacuum Leaks may now be detected by a new ionization gage tube
which permits one gas to pass while holding back all others, according to a release
issued last month by RCA. The new tube, RCA1945, is sensitive to hydrogen only.
It features a palladium plate which, when hot, is porous to hydrogen but acts as
a vacuum-tight barrier to all other gases and vapors. In operation, the tube is
connected into a vacuum enclosure or system to be checked for leaks. A tiny jet
of hydrogen is then played over the outside areas of the suspected system. Any leaks
will suck in the hydrogen which then runs down to the tube, passing through the
palladium plate and causing an increase in the ion current inside the tube. This
increase in current is amplified and indicated on a microammeter. Tiny leaks, so
small that molecules of air barely pass through them, can be detected by the tube,
which is sensitive enough to detect an increase in hydrogen pressure of less than
0.0000001 mm of mercury.
Under the plan, television receivers are delivered, installed, and picked up
anywhere in the metropolitan area.
FM Production is on the increase, Arthur Freed, treasurer of
the FM Association, reported last month. Between 15 and 20 manufacturers who have
produced only AM receivers up to the present expect to start manufacture of FM sets
before the end of the year, he said.
According to the same report, more than 700 FM stations will be in operation
before the end of the year, and 80% of the country's population will be within range
of at least one FM station.
Posted August 5, 2020