Monthly Archives: November 2019

1919 Aeronautical – Radio Wedding

We’ve previously reported two aeronautical weddings via radio, in April 1922 and June 1922.
Those, however, were not the first, since the wedding of Lt. George Burgess and Emily K. Schaefer took place in 1919. The bride and groom were in one plane, piloted by the groom. The minister, Rev. Dr. Alexander Wouters was in another plane piloted by best man Lt. Eugene Barksdale. The event took place at the Police Field Day festivities at the Sheepshead Bay Speedway near New York City.

A receiver hooked to a large public address system was in place on the ground, allowing the gathered guests to hear the entire ceremony. At 5:10 PM, the planes took off from the speedway. As those on the ground listened, the minister began to read the ceremony, and the couple exchanged vows. A few minutes later, one of the planes announced “we are coming down,” and the bride and groom landed to applause and waving hats. As the couple moved to an automobile, the bridal party rode past the stands while the police band played the wedding march.

Sadly, Lt. Burgess died in a firy plane crash in 1925 at New Salem, PA. After an airshow in Washington, he was flying to Dayton Ohio with an editor and photographer from the Dayton Herald. In a thunderstorm, the plane crashed to the ground, killing all aboard. His obituary described him as a wireless expert and instructor in radio airplane communications. He is buried at Arlington National Cemetery. The couple had two children. The bride died in 1969 at the age of 77.

The best man also died in an airplane crash in 1926. Barksdale Air Force Base in Louisiana is named in his memory.

The Möbius Resistor

Mobius resistor. Wikiepdia image.

Shown here in the November 1969 issue of Electronics Illustrated is Richard L. Davis of Sandia Laboratories, the inventor of the Möbius resistor, US Patent 3267406A.

Many youngsters will be familiar with the Möbius strip. It’s a three-dimensional object with one side and one edge. It is formed by taking a strip of, for example, paper, making a twist, and then taping the ends together. To prove that it has one side, the young scientist can draw a line down the middle. Eventually, the line will connect up, but only after covering “both” sides of the strip, in effect proving that there is only one side. The strip can also be cut along that line, which will form another strip, this one non-Möbius.

Davis used the Möbius strip to form a resistor. His strip of paper was coated with foil. When it was attached together. The outside of the strip formed a continuous conductor, and connections were made directly opposite. The result was that current was flowing on the outside of the strip, but in opposite directions. Therefore, the magnetic fields cancelled out, making the resulting device non-inductive. This proved useful at UHF, since the stray reactance of a resistor would otherwise be very significant at those high frequencies.

Students looking for an interesting science fair project could make either a Möbius strip or a Möbius resistor. A student will almost certainly get a participation ribbon by making the strip and then unsuccessfully attempting to cut it in half. But more advanced students, armed with an inexpensive RCL meter, can get the blue ribbon by showing that the inductance disappears by adding the twist to the strip.

The Battery is Dead!

You can say one thing for this woman: She had her priorities in the right place. The battery in the radio was dead, so there was nothing to do but go home. The cartoon appeared in the November-December 1949 issue of RCA Service News. It was reprinted from the New York Herald Tribune, apparently the August 10, 1949 edition.

Of course, if her dealer had heeded the advice on the next page and sold her genuine RCA batteries, this probably wouldn’t have happened.

Homemade Radio Telescope: 1959

The English high school students shown here in the November 1959 issue of Electronics Illustrated put together this Radio Telescope, at a total cost of about $40. Led by sixteen year old Doug Miller, the students at the Dartford Grammar School near London had already pulled in signals from the Milky Way, the sun, and the constellation Sagittarius. Parts for the receiver came from donated a donated TV set.

1919 Forest Service Heliograph

One hundred years ago, the forest ranger shown here is acting as “lookout man” atop some Western peak. As he watches for forest fires, he has at his disposal detailed maps of the area, as well as two means of communication. When he spots a fire, he can call in the bearing to headquarters on the telephone. To communicate with other spotters in areas too remote for a phone, he has the heliograph. On clear sunny days, the device had a range of up to 45 miles.

The first Forest Service heliograph units had originated with the Army Signal Corps, but more compact units suited to forest fire fighting were procured. Seven rangers were initially trained. Even though they had no prior knowledge, they became proficient operators in a very short time.

While Morse Code could be used, it was found that the Myer Code, shown below, was more reliable for visual signaling. The letter P, for example, is 1211. The one indicates a long flash, and the 2 indicates two short flashes.

The top photo appeared in the November 1919 issue of Electrical Experimenter. More details of the system can be found in a 1914 Forest Service Publication, Systematic Fire Protection in the California Forests. The heliograph instrument consisted of a mirror, which was oriented so that it reflected the sun on the receiving station. A shutter in front of the mirror was used to key the beam on and off. To call another station, the sending station would send a quick succession of flashes until acknowledged. Then, each station would turn on a steady flash to make adjustments. When the mirrors were in place, the sending station would proceed with its message. The average speed of transmission was found to be about four words per minute.

Plans for a simple heliograph can be found at an earlier post.

1944 Three Tube Regen

The young man shown here is pulling in the short waves thanks to a simple receiver designed around wartime parts shortages. The set used three tubes, which could be types 30, 199, or 201-A, obsolete tubes used by older battery sets. It featured two stages of audio amplification, and could drive either headphones or a small speaker. It pulled in shortwave signals from 160 to 10 meters with homemade plug-in coils. The detector was regenerative, with a variable capacitor controlling regeneration.

If B batteries were unavailable (a likely scenario given wartime shortages), then the transformerless battery eliminator shown here could be used. The set appeared in Popular Mechanics 75 years ago this month, November 1944.

1939 Mobile Rig

Shown here in the November 1939 issue of Radio News is a mobile installation dubbed the “Diplomatic,” which could be used by hams, or also for other mobile applications such as police radio. It is shown here in a 1939 Pontiac, but the same equipment is also shown mounted in a Chevy. The receiver, a Howard 438, is tucked away in the glove compartment, and most of the transmitter is located in the trunk. The dial on the dash is hooked to a stepper relay in the trunk, and is used to turn on the filaments and turn the bandswitch.

BSA – NBC Hook Up, 1939

Eighty years ago this month, the November 1939 issue of Boys’ Life shows Boy Scouts lending a hand at NBC radio stations. The images here are taken from network headquarters in New York, as well as WMAL Washington. The magazine shows scouts with Lowell Thomas. And Scout Stan Groner of Troop 248, Bronx, NY, is shown with Charlie McCarthy wearing a scout uniform, although it’s unclear whether McCarthy could pass the Tenderfoot requirements.

Philco Safari Portable TV – 1959

Sixty years ago, Santa was getting ready to deliver something new–a transistorized, battery operated television, shown above in the November 1959 issue of Popular Mechanics.

The Philco “Safari” model played a full four hours on its built-in rechareable battery, and could also operate on standard AC power. The set had a 2 inch picture tube, but optical magnification increased the size to 80 square inches. You can read more about the set at this link.

The November 1959 issue of Electronics Illustrated, shown at left, also chimed in with a feature about the set, as well as a battery operated 17 inch set which Emerson expected to have on store shelves the next year.

FCC Radio Intelligence Division: 1944

Shown above, from the November 1944 issue of Popular Mechanics, is one of the operators at an FCC Radio Intelligence Division monitoring stations. He was rotating an antenna capable of narrowing down the incoming signal to one degree, in order to track down a clandestine transmitter somewhere in the U.S., or even abroad.

The majority of operators were hams, and they had the procedure down to a science. They scanned the bands looking for unfamiliar signals. As soon as an unknown station was heard at one station, other stations were immediately notified by teletype and took bearings. Those bearings were then sent to Washington for a fix. At that point, one of 50 mobile units was notified, and would sniff out the transmitter. Finally, an RID man would find the exact location on foot. And as shown below, they would then raid the offending location, presumably with FBI men accompanying with the machine guns.

Before the war, there was little need for such extensive monitoring. But from 1940 to the date of the article, over 9000 cases of unlicensed and subversive transmitters had been spotted. Over 200 spies had been rounded up in South America thanks to RID bearings.

Some transmissions were high speed code, but the stations were equipped with recording devices, and transmissions could be played back at a lower speed. The stations were also invaluable for locating downed aircraft, both military and civilian.

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