Monthly Archives: July 2019

Trees as Antennas: 1919

1919JulPS1A hundred years ago this month, the July 1919 issue of Popular Science reported on the seemingly promising work done to date on using trees as radio antennas. The Signal Corps had been working on the problem during the War, and there was hope that explorers, farmers, lost Army units, or downed aviators could be in contact with the outside world as long as they were in the neighborhood of a good sized tree. The article reported that European stations had been pulled in with trees, and various methods of making the hookup were discussed.



Radio Craft First Issue, 1929

1929JulyRadioCraftAs we previously reported, this month marks the 100th anniversary of Radio News, which first appeared under the name Radio Amateur News. The magazine was founded by Hugo Gernsback, and was published by the Experimenter Publishing Company. That company went bankrupt ten years later, but the magazine continued, sans Gernsback.

Undaunted, Gernsback formed the competing Techni-Craft Publishing Corporation, and put out the first issue of Radio Craft magazine 90 years ago this month, July 1929. The two magazines competed and prospered for decades thereafter.



1959 Carrier Current Transmitter

1959JulElecWorldCarrierCurrentSixty years ago this month, the July 1959 issue of Electronics World carried the plans for this carrier-current transmitter. The set was billed as a “wireless neighborhood baby sitter.” Parents in the author’s neighborhood needed something to participate in bridge sessions and “kaffe klatches” while the baby napped at home. To avoid stringing wires from house to house, he put together this carrier current transmitter. It would cover all houses on the same transformer and could be heard on the host’s standard AM radio. To keep it legal, the author recommended checking to make sure that the signal didn’t go further than about 50 feet from the power lines. If the signal was too strong, then a smaller value for C19 should be used.

And when the kids got older, he suggested that it could be turned into a neighborhood broadcast station by adding a phono input in addition to the mike.



Raytheon Tubes: 1939

1939JulRadioRetailingThis ad, from the July 1939 issue of Radio Retailing, offers the reminder that your choice of tubes might be a matter of life and death. And if it is a matter of life and death, you should go with Raytheon tubes, just like many hospitals.



Scouts at 1939 World’s Fair

1939JulyBLCoverThe cover of the July 1939 issue of Boys’ Life, shows U.S. Boy Scouts at the 1939 New York World’s Fair.  Scouting at the Fair consisted of a camp in the “Government Zone,” near the pavilions of the various countries represented.  The camp would accommodate four troops of 33 scouts and 4 leaders.

At any given time, a third of the scouts were sightseeing at the fair, a third were on duty at the camp itself, and the other third were performing service for the Fair.

During the fair, a citizenship ceremony, officiated by U.S. Supreme Court Justice Owen Roberts, was held for a group of former scouts who had just turned 21 years old and were being naturalized as U.S. citizens.



Wartime Tube Price Ceilings

1944JulRadioCraft1These wartime burglars, shown in the July 1944 issue of Radio Craft, know where the good loot is, and it’s inside the radio, in the form of the tubes. Much to the consternation of radio owners and servicemen, many needed tubes were hard to come by.

The prices were reasonable, if you could get them. This is because of wartime price caps, as shown in this table in the same issue of the magazine. The 12SA7 that these crooks were about to nab had a maximum price of $1, but they knew that it would fetch more on the black market.

1944JulRadioCraft2



USFS Portable Phone, 1919

1919JulPSA hundred years ago, the U.S. Forest Service had the latest in portable telephones, as shown in the July 1919 issue of Popular Science.

This ranger is shown carrying the set, which weighs in at a featherweight 30 pounds. The bottom compartment contains the batteries, with the normal telephone transmitter and receiver in the top compartment. A magneto is included to ring the phone. Upon spotting a fire, the ranger races to the nearest phone line and hooks up the instrument. He gives the magneto a turn, which alerts the other phones on the line, and the fire gets reported.

But what if the other rangers have stepped out away from the phone? That’s where the middle shelf comes in. It contains a loud klaxon which would echo through the forest. If there’s no answer, the ranger switches the dynamo to DC to drive the klaxon and gives it another spin. The sound is presumably heard for miles around, his colleagues pick up the phone, and the fire gets reported.



Dance Any Time: The Victrola Is Always Ready

1919JulPSToday, the ability to listen to music is something we take for granted, and it has been for a little over a century. But for most of human history, you could listen to music only when there was someone around who was able to play it. In other words, most of the time, if you wanted music, you had to make it yourself.

A century ago, the phonograph was already well established. But as this ad shows, most people still remembered what it was like before. The ad appeared in the July 1919 issue of Popular Science.



1944 TL-122 Flashlight

1944Jul21MilJourOn this day 75 years ago, the July 21, 1944, issue of the Milwaukee Journal carried this ad from Schuster’s Department Store for this military surplus flashlight.  It came complete with batteries and bulb for $1.99.

Because of small mars or scratches, the flashlights were rejected by the government, but their loss was the public’s gain, since a shipment had just arrived.  The ad bears the name “Micro Light,” which presumably means that the flashlights were manufactured by the Micro Lite, one of the four manufacturers of this design, the TL-122.  More history of the flashlight can be found at this site.