News Briefs, December 1964 Radio-Electronics

"Semipermanent" magnetic memory is reported here in this 1964 Radio−Electronics magazine news item. The term semipermanent is an awfully good, clearly confusing, but seriously funny example of an oxymoron, akin to jumbo shrimp, old news, random order, and unbiased opinion. An electronic switching system is announced which will replace the massive network of electromechanical switches in the nation's telephone system. Once implemented, the cacophony of clicking relays heard inside the switch rooms containing thousands of of the noisy little buggers would go silent. I remember being in such a facility in the mid-to-late 1970s where the electromechanical relays were still being used, so it was well over a decade before a total switchover (see what I did there?) was completed. Also covered was a computer built by Univac that used fluid amplifiers (literally a fluid, including air). Also, there was news of the "World's Greatest Amateur," John L. Reinartz, W1XAM, having attained Silent Key status. I provided the color.

An electronic telephone-switching system will soon begin to replace present electromechanical systems in Bell Telephone offices, according to a report by Bell Telephone Labs and Western Electric engineers to a gathering of the press at Holmdel, N.J. The new system will offer a variety of telephone services not usually possible with the present systems. Among the advantages will be:

Abbreviated dialing, by which frequently called numbers can be reached by dialing an abbreviated two-to four-digit call instead of the regular long one.

Call transfer, which means that a person can dial a code and then the number of a nearby telephone. This will cause all his incoming calls to be transferred to that telephone.

Also available will be a signal which will tell a person telephoning that another call is trying to get through.

These, and other services now not even thought of, may be possible because the new technique uses a program control system of magnetic memories. Instructions for providing services and processing telephone calls can be modified or removed and new ones added by simply removing memory cards and "rewriting" the information on them. In today's system it would probably be necessary to rewire systems to provide additional services.

The electronic switching system will begin operation shortly in Succasunna, N.J., followed by electronic central offices on a limited basis in New York City, Washington, D.C., and Norfolk, Va. All new offices will use the electronic switching system, and equipment will be replaced gradually in existing offices.

The new system reduced to pictures. Line sensors scan all phones served by the office every tenth of a second, detect a call far service when phone is lifted off hook, alert the executive section (central electronic control), which goes into the program stare to set up the call, passes the command to the switching network, and the talking path is completed (to the lower telephone). Central control is a computer which uses approximately 30,000 transistors and 45,000 diodes. It works with two memories, program store and the call store. The program store is a semipermanent magnetic memory that contains all long-term instructions (such as haw to set up call transfers, etc.) The call store is a short-term memory which would be used, for example, for data having to do with a particular call.

How the intensification system works. The numbered callouts are self-explanatory, with the exception of 5 and 7, which refer simply to large-aperture optical lenses.

Experimental Computer Has Fluid Amplifiers - RF Cafe

UNIVAC engineer R. S. Gluskin attaches a plastic tube to one of the elements in the experimental digital computer that works with fluid amplifiers and air.

A technique that will make it practical to increase the magnification of an electron microscope from 200,- 000 times to 2,000,000 times was described by RCA at a press conference in Princeton, N.J. (At this magnification, a man's foot would be 400 miles long.)

By using image intensification and television projection, it is possible to use a much weaker beam in the electron microscope itself. Heretofore the microscope could not be used to its full capability, because in many cases the specimen being examined would be destroyed by the beam. Now, by intensifying (amplifying) the visible image, it is possible to start with a much weaker image .

Another important advantage is that the contrast of an image can be increased beyond what would be possible with the straight electron microscope. A contrast control, not greatly different from that in an ordinary television set, can bring up the contrast. Contrast can sometimes also be improved by reversing the image making it a negative instead of a positive -something that couldn't be done with the old electron microscope.

To produce these effects, the original electron microscope is focused on a phosphor screen at the original viewing point. From here it moves through a high-speed lens with a two-stage image intensifier. An image intensifier incorporates a photocathode, on which the image is focused, and which then produces electrons in the pattern of the visible image. These are accelerated to a screen where they produce an image of the same size but brighter. In the two-stage intensifier, this screen is a second photocathode, and the image is intensified again.

It is then focused on the camera tube of an image orthicon camera, amplified through special video amplifiers and projected on the TV screen.

The equipment also includes a video tape recorder, so that permanent records can be made. The apparatus is in production form, ready to be delivered, either as complete equipment or as an addition to existing electron microscopes.

Air flowing to 250 molded plastic switching elements through a complex network of channels enables a new, experimental computer to perform basic computer functions. Developed by Sperry Rand Corps, Univac Div., the new computer is far from being a practical model, having a capability of only four instructions and four words of memory. Each word is four bits long.

The fluid amplifier on which this computing system is based is a device that somewhat resembles an electronic triode. A jet of fluid - which may be air - is propelled from a nozzle or cathode toward a collector, which may be placed to intercept half the stream. A small jet of fluid is directed at the base of the main stream, at right angles to it. The relatively strong main stream is deflected by the small jet, which uses little energy, so the device amplifies. (See Radio-Electronics, August 1960, p. 56).

The fluid amplifier has already been used practically. The Army has developed a mechanical heart based fluid-amplifier principles. The same principle has been used for large hydraulic valves that work without moving parts. The Sperry Rand device, however, is the first attempt to use it as a computer, where it may eventually be practical in applications where high speed is not needed. Fluid-operated circuits can be constructed for a small fraction of the cost of conventional electronic computer circuitry. They are likely to be more reliable and can withstand higher and lower extreme temperatures, as well as nuclear radiation.

John L. Reinartz, "World's Greatest Amateur," died Oct. 6 in California at the age of 70.

He was known to a generation of amateurs and experimenters as the inventor of the tuning circuit that was the basis for the majority of short-wave receivers in the '20's, as a pioneer in short-wave communications and as a researcher who played an important part in exploring the regions of increasingly higher frequencies.

Reinartz, though of French descent, was born in Krefeld, Germany, and came to the United States at the age of 10. His parents settled in South Manchester, Conn. He became interested in radio while he was still in school, and continued his hobby while working as a clerk in a dry goods store and later in the electrical department of a silk mill.

In 1923 he took part in the first two-way radio contact across the Atlantic, with Leon Deloy of the French amateur station 8AB, on approximately 100 meters. When the MacMillan National Geographic Arctic Expedition was started in 1925, he was selected by Capt. Donald B. MacMillan as operator because of his capabilities and experience in short-wave radio.

Later he joined the technical staff of the amateur magazine QST, and also contributed many articles to other publications. Reinartz had many opportunities to become wealthy on his inventions, but remained a strict amateur, dedicating his discoveries to the public and refusing to allow major radio companies to use his name in advertisements.

During World War II he was in charge of radio training for the Naval Communications Reserve, with the temporary rank of captain. In 1949 he joined Eitel-McCullough, a tube manufacturer well known to hams. He headed the company's amateur service department until his retirement in 1960.

Mr. Rienartz held an earlier call, 1QP, before making W1XAM famous throughout .the world. After moving to the West Coast, he held the call K6BJ. He was a member of the Explorers Club of New York, Fellow of the IEEE, member of the American Polar Society and an associate member of the Naval Institute.

Citizens-Band interference to television is becoming serious in metropolitan areas. The New York office of the FCC reports that the number of complaints of CB interference to TV has risen to 900 a month. Owners complain of jiggling lines in the picture, and "adolescent voices" on the sound channel.

Color television plans in Great Britain will probably not come to fruition until 1967, and the BBC expects to use its noncommercial second channel for color programming. Set manufacturers will probably use RCA tubes.

News BriefsDecember 1964 Radio-Electronics

News Briefs
December 1964 Radio-Electronics