Category Archives: Radio history

1944 Code Practice Oscillator

1944janradiocraftThis simple idea for a code practice oscillator appeared in the January 1944 issue of Radio Craft magazine.

No doubt inspired by wartime parts shortages, the audio feedback loop could be created with an old telephone receiver and microphone placed next to each other. The idea was sent in to the magazine by one Mr. Ivan H. Walker of Mt. Horeb, Wisconsin.



WLS Chicago, 1946

1946novsponsorwls

In this ad from the November 1946 issue of Sponsor magazine, WLS Radio in Chicago reminds its potential advertisers that it is the radio home of tomorrow’s friendly audience.

In July of that year, 2000 boys and girls from every county in Indiana were in the studio audience of the WLS Dinner Bell Time broadcast, “a program familiar in their homes from babyhood.” They were attending the annual 4-H Round-Up being held on the campus of Purdue University.

WLS presented the plaques for outstanding 4-H achievement, all broadcast live over the station’s 50,000 watt Chicago blowtorch. People in Illinois, Indiana, Michigan, and Wisconsin considered the station “one of the family,” and its complete weather, market reports, news, and down-to-earth entertainment expemplified the quiet neighborly way that WLS served both today’s and the future’s friendly audience.



RCA Victrola Model V-215, 1941

1941nov17life

This ad appeared in Life Magazine 75 years ago today, November 17. 1941. Victor Record recording artist Rose Bampton is listening to records on the RCA Victrola Model V-215 radio-phonograph console.  The nine-tube set provided 12 watts to the 12 inch speaker. In addition to the standard broadcast band, it tuned two shortwave bands, 2.3-6 MHz and 9.3-15 MHz. You can view a nicely preserved example of the set at this link.  The set had an original retail price of $214.95.

As the ad points out, the set features the “Magic Brain” automatic changer, and points out that the Magic Brain does all the work–you just sit back and listen. It also points out that the changer has “no needles,” meaning that it had a sapphire stylus and ceramic cartridge rather than “old-fashioned needles,” and that the total weight of all moving parts on the tone arm was “less than the weight of a postage stamp.”

Mezzo-soprano Rose Bampton performed with the Metropolitan Opera from 1932-1950. She died in 2007 at the age of 99.



Emerson Model 330, 1941

1941nov16pghThis ad for a 5-tube supereheterodyne broadcast radio appeared 75 years ago today in the November 16, 1941, issue of the Pittsburgh Press.

The set sold for $14.95 (complete, no extras), or could be bought on time for a quarter down and fifty cents a week.

The set appears to be model 330, which can be seen at the Radio Attic Archives.  It was a standard “All American Five,” with a tube lineup of 12SA7GT, 12SK7GT, 12SQ7GT, 50L6GT, and 35Z5GT. A schematic and more photos are available at the Radio Museum.  While the set’s tuning range didn’t extend much above the broadcast band, it was billed as easily receiving police calls, as well as distant stations.



1926 Popular Science Crystal Set

1926novps

Ninety years ago this month, the November 1926 issue of Popular Science showed how to assemble this crystal set for the radio beginner, and offered a number of possible variations depending on the listener’s location and available stations.

The article noted that millions of Americans lived within five miles of powerful stations, but a surprisingly large number had not yet taken an interest in radio. But this simple receiver was billed as a mighty good way to get started, and predicted that many builders would eventually decide to upgrade and build a vacuum tube set. Parts selection kept in mind that many of the components, such as the variable condenser, could be used in the new set.

The author remarked that he had a friend who had a good five-tube set, but kept the old crystal set around for times when he wanted to listen to the radio alone. The headphones masked outside sounds, and he didn’t have to worry about wear and tear on his tubes.

The article suggested modifications of the antenna coil depending on the location and number of stations. It gave instructions on tuning. While moving the dial, you would adjust the crystal for the first hint of sound. When that was found, you would tune the dial for maximum sound, and then adjust the crystal for maximum volume. The crystal position could usually stay put for weeks. To prevent vibrations, the author suggested placing the set on a piece of cloth.



Dutch Reagan, WHO 1936

1936nov14radioguide

Eighty years ago today, the November 14, 1936 issue of Radio Guide carried a profile of the man who would, 44 years later, be elected President of the United States, Dutch Reagan.

As recounted by the magazine, Ronald Reagan walked into WOC radio in Davenport, Iowa, in 1932, looking for a job. The station was at the time synchronized with WHO Des Moines. The program director, Peter MacArthur, asked if he knew anything about football. When Reagan answered in the affirmative, MacArthur told him to stand by a microphone and imagine that he was at a game. The program director listened amazed for fifteen minutes before telling Reagan, “you’re broadcasting the Iowa-Minnesota game!”

When WOC and WHO split in 1932, Reagan went with WHO, where he broadcast the Chicago games by telegraphic report.

The article describes the future president:

He is over six feet tall with the pro- verbial Greek -god physique: broad – shouldered, slim-waisted and a face that would make Venus look twice before running to her man Zeus! And then he can talk, too.  Dutch has a smooth -running “gift o’ gab” which never seems to falter, never is at loss for the right word. In short, he has quick wit and a nimble vocabulary, and large, too.

It noted that during his days at Eureka College, where he lettered in several sports, he never allowed anyone to call him Ronald, even though it was his name.  The magazine also seemed to think that the young announcer had a future:

But there are new things beckoning. One is a career with the networks.
Like any ambitious announcer, Dutch, who never uses quotation marks about his name, has high hopes toward becoming the Husing or the McNamee of the airwaves, 1937 style. Watch him; he’s stream-lined. He might do it.



WGEA and WGEO, Schenectady, NY, 1941

1941wgea

Shown here as it appeared 75 years ago is a view of 100 kW shortwave stations WGEA and WGEO, the General Electric station at Schenectady, New York.  The picture appears in the November 1941 of FM Magazine, along with an extensive look at the technical details of the stations, as well as those of GE’s sister station in San Francisco, KGEI (about which we wrote earlier).

The station had its start in 1925 with an experimental license under the call sign W2XAD. When the FCC deemed shortwave broadcasting to be sufficiently developed for commercial service in 1939, the station went on the air commercially.

GE received over 30,000 pieces of mail per year, and prepared its programs based on listener preferences. In addition to English, the stations had regular programs in Spanish, Portuguese, French, Dutch, Czech, and Chinese.

Frequencies used at the time were 6190, 9530, 9550, 9670, 15330, and 21590 kHz. Directional antennas beamed programs from Schenectady to Central America, Brazil, Europe, Argentina, and North Africa, and from San Francisco to South America and Asia.



Canada Carries On: 1941

1941nov10bc

Seventy-five years ago, the United States was less than a month away from entering the war, but Canada had been at war with Germany since 1939.  In this ad from this date’s issue of Broadcasting magazine, November 10, 1941, the Canadian Broadcasting Corporation reminded potential American advertisers that Canada was carrying on.  Despite wartime conditions, industry was at capacity, new factories were coming online, employment was at a peak, and most important for advertisers, retail sales were showing gains.

The CBC was serving wartime duties, and it reminded advertisers that it provided complete broadcast services to reach the Canadian market.



1916 Spark Coil

1916novelectexp

One thing that sometimes mystifying when looking at diagrams of early spark transmitters is that the descriptions often lack much detail as to the most important component, the induction coil or spark coil. A good description can be found in Electrical Experimenter magazine, November, 1916, from which this illustration is taken.

The “coil” is really two coils, plus an interrupter, and the operation is described here:

When the primary switch of such a coil is closed, the battery current passes through the first winding on the core and magnetizes it. This attracts the iron armature on the vibrator spring, as shown in Fig. 1, and when this spring breaks contact with the platinum tipped screw in front of it, the circuit is opened. At this juncture there is induced in the secondary winding a very powerful current. The spring-actuated vibrator returns to its former position in the fraction of a second and the process is repeated all over again.

The referenced schematic diagram is shown here:

1916novelectexp2



Radio Bargain House, Birmingham, AL, 1941

1941novradioretailing1

Seventy five years ago this month, Pearl Harbor was still a month away, and the end of civilian radio production was still five months away. But radio retailers were starting to feel shortages, since many parts were in short supply due to wartime material priorities, and in some cases, the numbers of new sets available didn’t meet demand.

This led many retailers to take a closer look at selling used sets. Trade-ins were often viewed as a headache, and little effort was made to realize a profit from them. But the wartime economy made many retailers consider selling used radios. The November 1941 issue of Radio Retailing carried advice from the experience of M.M. Law, the proprietor of Radio Bargain House of Birmingham.  Law got into the radio business by accident when running a hotel.  A hotel guest turned a radio over to him for sale, and he placed a classified ad in the paper.  He received fifteen calls in response to the ad.  When he eventually lost the lease on the hotel, he decided to get into the radio business.

1941novradioretailing2Law typically made a net profit of about $2 on each set.  He often bought in bulk from other dealers looking to unload their trade-ins, sometimes as low as $1 per set.  He typically invested about $3 fixing up each set, and quickly sold many for $6.95.  He estimated that his average sale was between $12 and $15.

He continued advertising in the classified ads, since his experience was that this was where bargain shoppers looked.  He always kept a set outside his shop, marked “today’s special,” and reported that he would often sell this set, with the buyer not bothering to look for others.  In other cases, however, the set outside would entice a buyer to come in the store to buy a better set on the floor.