Category Archives: World War 2

1921 Creed Automatic Radiotelegraphy System

No. 7W/3 Reperforator, manufactured by Creed and Company Limited, Croydon, London, England, 1925

Creed No. 7W/3 Reperforator (1925). Image courtesy of Science Museum Group Collection, © The Board of Trustees of the Science Museum, U.K. released under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 Licence.

No. I.T. Morse Tape Printer (1925). Image courtesy of Science Museum Group Collection, © The Board of Trustees of the Science Museum, U.K., released under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 Licence.

The two devices shown above represent a hundred year old method of automatically decoding International Morse Code. They, along with the sending device, are described in the March 1921 issue of Radio News.

At the sending end, the message is typed on a typewriter-like keyboard and punched onto a paper tape. An example of the tape is shown below. It’s not immediately obvious that the tape contains Morse code, but upon closer observation, it is. A “dot” is indicated by one hole directly above another hole. A “dash” is indicated by two holes that are slanted. Once you see this, the Morse code is obvious. The first word shown here is “the.” The first two holes are slanted. This is a single dash for the letter T. This is followed by four sets of holes, one directly above the other–four dots, for the letter H. Next, there is a single set of vertical holes, another dot for the letter E.

Once this tape is produced, it is sent through another machine which keys the transmitter and sends the Morse signal over the air.

At the receiving station, the two machines shown above are used to receive and print the message. The reperforator (top) connects to the receiver and produces an exact duplicate of the paper tape. Then, the paper tape is fed into the Morse Tape Printer, which prints the message on a paper tape.

The process was known as the Creed Automatic System, named after inventor Frederick G. Creed, an important figure in the development of the teleprinter. At the beginning of the 20th Century, Creed was told my none less than Lord Kelvin that “there is no future in that idea.” Undaunted, he managed to sell twelve machines to the British post office in 1902. The 1921 machine described for use with wireless telegraphy appears to be a variation of that device.

By the late 1920s, the company was producing teleprinter equipment using a variant of the five-bit Baudot code. The company became part of IT&T, and Creed retired from the company in 1930. Among his later projects was the “Seadrome,” a floating airport which could be placed along international air routes. The project is described in a March 1939 article in the Glascow Herald, and was undoubtedly a casualty of both the War and increased aircraft range. The Seadrome is the subject of US Patent 2238974, applied for in February 1939 and granted in April 1941.

The images above are copyrighted and provided courtesy of the Science Museum Group, U.K., where they are on display, and released under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 Licence.

Radio Hams Practice for War: 1941

In 1941, the ham radio operator shown here was asked how long he would need to get his portable station into operation in the field. “Six minutes is the average time,” he replied. The officers asking the question were skeptical, but they watched as he opened his suitcase, hooked up a car battery, hammered in a ground stake and slung the antenna into a tree. He then tapped out a message to the control station fifteen miles away.

This was but one of the tales recounted eighty years ago this month, in the March 1941 issue of Popular Mechanics, in an article entitled “Radio Hams Practice for War.” It detailed the work of the 1800 member Army Amateur Radio System and pointed out that in time of war, thousands of trained hams would go into the military for active duty, and others would take on civilian duties such as listening for clandestine stations.

In another exercise, hams were asked, “your radio transmitter is completely smashed by a falling chimney. How long will it take to borrow an old broadcast receiver from a neighbor and build a new transmitter from its parts?” Another ham was ordered, “simulate destruction of your main transmitter. Rig up your emergency equipment and report back on the air as soon as you can.”

The article detailed a number of ways in which hams were “preparing themselves against a possible ‘M’ day.”

Postwar Radio Retailing: 1946

Shown here on the cover of Radio Retailing 75 years ago this month, February 1946, this couple are taking home their first postwar radio. New civilian radios were coming back on the market after a long absence, and there was probably still a shortage, as evidenced by the crowd clamoring behind them.

The magazine reminded dealers, however, that the time would soon come when customers would stop searching for radios. Instead, they would soon be going from store to store choosing. It warned against complacency. Even though it was currently no real task to sell anything, the dealer’s goal should be to make a customer of every shopper. In particular, customers would appreciate a little extra courtesy and consideration.

Selling a scarce item with the same degree of interest that would be called for in a competitive era would have the result of making friends and getting free advertising for his goodwill.

The day would soon come when the dealer would have to fight for every dollar, and attractive selling methods now would go a long way to bring in those dollars.

Taking Requests by Signal Lamp: 1946

WW2-era signal lamp. Wikipedia photo.

The taking of requests has been a long-standing tradition in the broadcasting industry. Most typically, the requests come in by phone, but other methods are possible, as shown in this item from Broadcasting magazine 75 years ago today, January 21, 1946.

WXLH, the Armed Forces Radio Service station in Okinawa, which had come on the air on May 17, 1945, carried a request program, originally slated to run 45 minutes six nights a week. The program was widely popular with servicemen, and requests poured in by telephone, teletype, mail, and in person.

Buckner Bay. Wikipedia image.

Left out, however, were the sailors on the hundred or more ships anchored in Buckner Bay. To accommodate them, on Christmas, some of the station’s engineers rigged up a 500 watt bulb on a stand and pointed it toward the bay. They blinked out a message that the station would be happy to take Navy requests as well.

The sky lit up within minutes with beams of light crisscrossing the horizon. AFRS and Signal Corps men dotted the hillsides and took down the requests.

Pearl Harbor

USS Shaw at Pearl Harbor. Defense Department Photo.

Today marks the 79th anniversary of the Japanese attack on Pearl Harbor, December 7, 1941. Here are links to some of our earlier posts marking that event:

Marketing Personal Portables: 1940

Eighty years ago this month, according to the December 1940 issue of Radio Retailing, everybody, including Santa Claus, stopped, looked, and listened to the new personal portables that had been hitting the market. When America entered the war, sourcing the required batteries would become an iffy proposition, but in the meantime, the sets were popular.

It’s quite possible that Santa got the idea from having lunch in downtown Denver. According to the magazine, the radio buyer of the Denver Dry Goods Company harnessed the power of “women paid to gossip” to sell the sets. You could put one on layaway for a dollar down and a dollar a week. Then, to drum up excitement, “certain shopgirls were loaned instruments, subsidized to play and talk about them during lunch in the smartest restaurants in town.”

The young women shown below are on their lunch break from their duties at the store at one of the aforementioned smart restaurants. For each sale they referred, they earned a one dollar commission.

According to the article, twenty radios were sold the first day, and “in this case, it paid to pay women to gossip.”

1945 One Tube Broadcast Set

Seventy-five years ago this month, the November 1945 issue of Radio Craft carried this circuit for a simple one-tube receiver for the broadcast band. The set used either a type 30 or 1G4 tube, with as little as 3 volts B+ on the plate. The circuit had been sent in to the magazine by Bill Buehrle, Jr., of Ferguson, MO, who reported that he was able to pull in a half dozen stations clearly from 25 miles away.

Even though the circuit was published after V-J Day, it’s likely that it was perfected while the War was still in progress with its attendant parts shortages. The author points out that parts weren’t critical. In addition to the tube and headphones, the circuit required only six manufactured parts, two resistors, two fixed capacitors, and two variable capacitors. The coils and the RF choke could be wound at home.

The circuit could be easily duplicated today. The tube is still readily available on eBay. The type 30 and the 1G4 are electrically identical, but my preference would by the 30, since its glass has the classic styling of the 1930’s era bottle, as opposed to the more “modern” octal style 1G4. It’s such a simple set that it would form the basis for an excellent science fair project. And with only 3 volts involved, it would even be a safe project. The original article contains some suggestions on how the circuit could be modified, so comparing some of these modifications would make the project very worthwhile. The young scientist needing to track down the parts will find some helpful leads on my crystal set parts page.

UN 75th Anniverssary

Photo, Minn. Historical Society, via Minn. Alumni Assn.

For better or worse, the United Nations came into existence on this day 75 years ago, October 24, 1945. The organization came about as the result of the conference in San Francisco that summer, while the war in the Pacific was still raging. Shown above is former Minnesota Governor Harold Stassen signing the charter as part of the U.S. delegation. At the time of his death in 2001, Stassen had been, for a number of years, the last living signatory of that document.

1940 RCA Ad

This ad showing RCA’s product lineup for 1941 appeared 80 years ago today, in the October 21, 1940, issue of Life magazine.

For those on a budget, the model 45X-1 for $9.95. The ad bills that set as having one police band, but in reality, it covers the broadcast band but with a bit of extended coverage to pull in police calls in many areas.

The most expensive of the table radios shown is the 18T for $49.95. That 8-tube set featured six pushbuttons and two shortwave bands for pulling in the war news from Europe. At the top of the line of the tabletop radio-phonos was the V-102, a 7 tube set which appears to be broadcast only, for $59.95.

For a larger view of the ad, from most browsers, click twice on the image.

1940 British One Tube Shortwave Regen

The plans for this simple one-tube wartime regenerative receiver appeared in the British Practical Wireless, October 1940. The author reports that nearly any triode can be used, and he suggests that if more than one is available, they should all be tried to find the best specimen.

The author reported that he was able to pull in many DX transmissions that evaded his friends. He attributed this not only to the sensitivity of the receiver, but also to his patience and possibly good location.

The author used an aluminum chassis, which he acknowledged might not be available. He noted that perforated zinc might be substituted, as long as good ground connections could be made.

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