Category Archives: Radio history

Radio’s Potential for Romance: 1921

1921AprRadioNewsIt’s likely that the readership of Radio News a hundred years ago was mostly young men who had been bitten by the radio bug.  The April 1921 issue carried this article entreating them to get their friends interested in the hobby. It pointed out that there were “many bright boys and young men who are spending their evenings in idleness or bad company simply because they haven’t found an interesting hobby.” The ideal hobby, of course, was amateur radio, and it was one that would lead to a big future for those who got in on the ground floor with a thorough practical knowledge of radio.

But there was more: “boys, there is an additional reason for getting interested in radio. The ‘reason’ being shown in the accompanying photographs. Some of you fellows may not have known it, but many of the fair sex have gone in for radio and more are taking it up all the time.”

That’s right. Amateur Radio was a veritable chick magnet!  “What could be more interesting than a radiofone conversation during a long, lonesome evening with a sweet-voiced girl on the other end?  Wait until the radiofone becomes more universal and we predict many a romance will be started just this very way.”

The promised photos include, at the lower left, an unidentified girl at her radio set, somewhere in Brooklyn. And at the lower right, a “girl amateur” is receiving some C.W. instruction at the Second District Radio Convention Exhibition.

The picture at the top of the page isn’t, it turns out, just a candid shot of two young women tuning in their crystal set while out for a walk. It’s actually a still from the silent film short feature “Eve’s Wireless“.

The article identifies the actresses as Peggy Brady and Alice Brady of the Ziegfeld Midnight Frolic, a somewhat risque rooftop after-hours presentation after the Ziegfeld Follies let out for the night.

You can view the entire film here:



1961 Automatic Lawnmower

1961AprRadioElecSixty years ago, this gentleman, probably Gordon Carlson of the DeVry Technical Institute of Chicago, made the cover of the April 1961 issue of Radio Electronics magazine by mowing his lawn automatically with this fully automatic electronic lawnmower. But this wasn’t a pie-in-the-sky idea concocted by a futurist. Mr. Carlson actually built the thing, and described the electronics in detail in the magazine. Since the mechanical details would vary from lawnmower to lawnmower, he left many of them to the reader. In this case, the automation was added to a Jacobsen Lawn King. But the basic idea was rather simple.

1961AprRadioElec3Buried a few inches under the lawn was an insulated wire carrying an alternating current. On front of the mower (shown in the inset in the lower right hand corner of the cover) were two pickup coils, one to the left, and one to the right. When the mower was directly above the wire, the induced currents would be equal, and the mower would proceed straight ahead. But if one current got stronger than the other, the signals would be amplified by the electronic circuit and would trigger a relay which would steer the mower to either the left or the right, using an electric motor coupled to the mower’s steering. To keep the machine from constantly hunting, a further refinement was added. If the mower was only slightly off course, the corrections would be made slowly. But if it got way off track, the steering motor would operate at high speed.

As a nod to safety, a limit switch in front of the mower would cause it to stop if it encountered an obstruction such as a toy, a pet, or a child. As shown in the likely staged photo below, this scheme could apparently be trusted.  I scoured news archives and found no reports of a young woman meeting her demise in a lawnmower accident in that time frame.

1961AprRadioElec2



1961 Marine Band Converter

Screen Shot 2021-04-06 at 11.54.45 AMNo, this device wouldn’t pick up music from the United States Marine Corps, but it would allow your car radio to listen in on the local maritime radio traffic on the 2-3 MHz marine band.

The project appeared in the April 1961 issue of Electronics Illustrated. It used a single 2N140 transistor as an oscillator on 3.5 MHz, when mixed with the 2-3 MHz signals, the output could be heard on the broadcast band. It was powered by a battery which was said to be good for hundreds of hours with the low current drain circuit.

The cost was said to be about $10, which would quickly be paid back with fresh fish. The idea was that by monitoring the traffic from commercial fisherman, the hot fishing spots would be revealed.

Screen Shot 2021-04-06 at 11.56.04 AM



If It Sounds Too Good To Be True . . .

1951AprRadioElecAt first glance, this radio kit sounds like a great deal. For only $2.95, including postage, it looks like you get a kit to put together an “All American Five” radio, for considerably less than what it would cost to purchase one already assembled.

When I saw it, I was a little bit dubious, so I read more closely. Sure enough, it looks like it includes all of the components. I was still suspicious, so I looked even more closely, to make sure that it was a real five-tube superhet, and not some kind of stripped down crystal set. But sure enough, it includes a calibrated tuning knob and a volume control knob. Yep, it sounds like the real deal, and it sounds like, as the ad announces, a good way to get started in radio.

I bet there were a few who came to the same conclusion and sent in their $2.95. But first, let’s read it one more time, very carefully this time.

For $2.95, you don’t get started in radio. You get started on this radio, but you don’t finish for that price.  They don’t furnish all of the components.  They furnish all but the components!  You get the cabinet, the chassis, name plate, the knobs (but apparently not the volume control or tuning capacitor), the back panel, and five tube sockets (but no tubes).  In their generosity, they even include four screws and three grommets.  But that’s it.  For the actual components, you’re on your own.

The ad appeared 70 years ago this month in the April 1951 issue of Radio-Electronics.  It was offered by the Lormel Products Co. of 10406 Superior Avenue, Cleveland, Ohio.  They don’t seem to be in business any more.



1941 CW Transmitter

Screen Shot 2021-04-05 at 1.21.22 PMEighty years ago this month, the April 1941 issue of Popular Mechanics showed how to put together this simple CW transmitter designed to cover five bands (160, 80, 40, 20, and 10 meters, since 15 meters wasn’t a ham band until after the war). Crystals for the transmit frequency could be used, or the crystals for 160, 80, and 40 would double easily. Plug-in coils were used to switch bands (and presumably, a 15 meter coil could be wound after the war).

The 20-watt transmitter was billed as suitable for the beginner. If the receiver in the photo above looks familiar, it appeared in the magazine’s January issue, and we previously wrote about it.  The transmitter, like the receiver, had a built-in AC power supply, this one using a type 80 rectifier.  The transmitter itself used a 6L6-G tube.  The parts for the set were said to be available in kit form from a number of suppliers, and would set the builder back about $13, plus tubes, coils, and crystals.

The new ham putting together these sets would be able to work only other U.S. stations, since there were already restrictions on working foreign stations.  And 8 months later, they would be off the air after Pearl Harbor, although the receiver would continue to pull in war news.

Screen Shot 2021-04-05 at 1.22.06 PM



1961 British AM-FM Portable: The Roadfarer

1961AprPracWirSixty years ago, the April, May, and June 1961 issues of the British journal Practical Wireless contained the blueprints and construction details for this ambitious project, dubbed the “Roadfarer.” The set was a completely self-contained portable that would tune the longwave, mediumwave, and FM broadcast bands. It would operate on batteries, but also included an AC power supply to give greater economy when close to the mains.

The magazine promised that the set would be found simple to build, thanks in large part to the use of printed circuit boards. A total of three boards were used, for the AM tuner, FM tuner, and audio amplifier.

The magazine announced prizes for the best constructional work carried out by readers. A panel of judges had been assembled from representatives of the firms whose parts were used in the receiver. Some of those firms kitted all of the parts needed to construct the set, and those were found in subsequent issues of the magazine.

Despite the announcement of the prizes, I wasn’t able to find any listing of winners in subsequent issues of the magazine.



US Post Office Airmail Radio System: 1921

1921AprPMA hundred years ago this month, the April 1921 issue of Popular Mechanics described the radio network of the U.S. Post Office Department. At a cost of $26,000, the post office had put together a string of 15 stations–10 owned by the post office, and 5 others shared with other government departments–to facilitate the carrying of airmail across the country.

65 airplanes were in use transporting 200,000 letters daily, and to manage the system and provide meteorological data, radio was necessary. The first one, shown here, was established at College Park, MD. Others were at Bellefonte, PA, St. Louis, MO, Omaha and North Platte, NE, Cheyenne and Rock Springs, WY, Salt Lake City, UT, and Elko and Reno, NV.

Work on the system had begun in 1920, and at press time, sixteen radio men were in the employ of the department. Plans were in the works to equip planes with radio direction finding equipment and radiotelephones.



TV Steeplejacks: 1951

1951AprPMThis gentleman, shown on the cover of the April 1951 issue of Popular Mechanics, is a lot braver than I am, but he was a critical part of the radio-TV industry.

Since TV and FM signals require line of sight propagation, antennas need to be up high, and steeplejacks were the men who made sure they were up there. According to the magazine, some of the employees were old timers used to working jobs up high, but some were young men. There were few accidents, because the one thing all workers had in common was that they could have only one accident.

In New York, the 1250 foot Empire State Building had just grown 222 feet with the installation of the antennas for five New York TV stations. The idea was to eliminate ghosts and extend the range 50 miles.

The magazine pointed out that the building came with a “spike” originally designed as a mooring spot for Transatlantic dirigibles. It came in handy providing a solid base for the antennas.



1961 Speed Mail

1961AprPESixty years ago, the U.S. Post Office tried something that Popular Electronics, in its April 1961 issue, called “Electronic Speed Mail.” The official name for the service was just “Speed Mail,” but it was an early hybrid of electronic mail (or more accurately, facsimile) and snail mail.

The Post Office Department envisioned having centers in 71 cities strategically located across the country. To write a letter that would be delivered the same day, a sender would write the letter on a special form provided by the post office, taking care to write only within the lines. The form was likened to the special “V-Mail” form of World War II, with which letters were microfilmed stateside and delivered to Army Post Offices where they were printed and delivered, or vice versa. In this case, the message form was sealed and deposited into the mails. At the local post office, it was fed in, still sealed, to a facsimile machine. The machine opened the mail, scanned it, and placed it into a sealed container. After the operator was sure that the message had been properly sent, the batch of message forms was destroyed.

The scanned message was then sent via the Echo 1 satellite to the closest post office to the recipient. There, the message was printed and sealed into a window envelope with only the recipient’s address and return address showing. Again, the entire process took place without human eyes seeing the message.

An example of the message blank is shown below. This one bears a message sent from Postmaster General Arthur Summerfield to Vice President Nixon, late in 1960. (Even though the message was sent crosstown in Washington, it was relayed via Chicago to demonstrate the service’s capabilities.)

When the Kennedy Administration took office, newly appointed Postmaster General J. Edward Day (best known for the creation of the ZIP code) was less enamored with the system, and no further efforts were made to promote it. The Western Union Mailgram service (“the impact of a telegram at a fraction of the cost”) was introduced nine years later in 1970, and allowed rapid mail service. Messages were sent by Western Union to the nearest post office, where they were printed and delivered the same day received.



1941 Portable Transmitter-Receiver

1941AprRadioNewsIn the April 1941 issue of Radio News, William D. Hayes, W6MNU, of Oakland, California, recounts that since he liked to build his own equipment and constantly improve as the state of the art progressed, he had amassed a large collection of perfectly good spare parts. To put them to use, he put together this transmitter-receiver. It was intended for portable use while vacationing, but could also be put to use as a backup rig from the home station.

The receiver employed a 27 tube as regenerative detector, with a 47 used for audio output to drive a speaker, mounted on the wooden front panel with a piece of window screen for protection. The receiver covered 70 through 550 meters in two bands. The author noted that tuning the broadcast band was a useful feature, since the set would be used on vacation. He reported that the simple receiver provided very good reception on the broadcast band.

A bandspread capacitor covered the 80 meter ham band perfectly.

The 80 meter transmitter was a crystal oscillator also using a 47 tube. The use of the same tube as used in the receiver was intentional, to minimize the number of spare tubes that had to be carried. With the type 80 rectifier tube, only three spare tubes had to be brought along.

The author reported that from his cabin in the Santa Cruz mountains of California, and with a 130 foot antenna only 10 feet off the ground, he made numerous contacts with California, Washington, Oregon, Idaho and Nevada.

1941AprRadioNews2