Seventy years ago, the British radio enthusiast who wanted to be the first on his block to own a transistor radio could do so, thanks to the plans contained in the February 1956 issue of Radio Constructor.

The portable set, dubbed the “Transistorette,” had been on display at a national radio show, where it had great interest.  As soon as transistors became available in Britain, the editors of the magazine got to work coming up with a practical circuit.  With a short antenna and ground connection, the set provided good loudspeaker volume on the medium wave band.  It was essentially a crystal set, with a three-transistor audio amplifier.  It ran off a 22.5 volt battery, and since transistors were new, the magazine contained a stern warning of the consequences of hooking the battery up with the wrong polarity.

Eighty-five years ago, the February 1941 issue of QST carried the plans for this two-tube receiver which covered 1.4 through 14.5 MHz. The construction article, which carried no byline, noted that it was customary for beginners to start with a two-tube regenerative receiver. This one, however, was a superheterodyne. Since it contained no IF amplifier, the detector stage was actually regenerative.

The article conceded that this seemingly combines the disadvantages of both. But this wasn’t really the case. By having the detector set to a fixed frequency, it could be optimized for stability, particularly because the frequency was low, the set using an IF of about 1600 kHz.

The total cost was $11, $1.50 of which was for the most expensive component, the dial. A 45-volt battery supplied the B+, and a filament transformer was used to provide the 6.3 volts. The article noted that both the battery and the transformer could be had for about $2.

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The illustration on the cover of QST 100 years ago this month, February 1926, looks fanciful, but it’s a real scene. The accompanying article contains an actual photograph of the structure, used by Dr. Greenleaf W. Pickard (1877-1956) in carrying out experiments on what we would today call the polarization of radio waves.

Dr. Picard discovered that short waves, unlike long waves, do not remain vertical after leaving the transmitter. The structure was located at Seabrook Beach, NH, and analyzed waves of 80, 40, and 20 meters. Most of the stations received were calling CQ on the ham bands, and a number of schedules were also made. A total of 379 stations were logged to gather the data, including a few Canadian and European stations.

The article concluded by requesting readers to submit reports. It cautioned that a mere list of “calls heard” would be of little use. What was needed was comparisons of vertical vs. horizontal receiving antennas.