Hints for Radio Experimenters
December 1937 Popular Mechanics

December 1937 Popular Mechanics

[Table of Contents] Wax nostalgic about and learn from the history of early mechanics and electronics. See articles from Popular Mechanics, published continuously since 1902. All copyrights hereby acknowledged.

In the early days of radio, many people built their sets from schematics and a box full of parts. Often, obtaining the required components was not such an easy task, either because of a lack of means of knowing what was available from suppliers or due to lack of availability of needed parts that were advertised as being ready for purchase. A lot of local electronics repair shops sold components, as did many hardware stores. Still, fabrication of one's own inductors, antennas, tuning capacitors and/or coils, chassis for mounting all the components, etc., was required. Accordingly, science and electronics magazines often ran a monthly feature presenting hints, kinks, tricks, and shortcuts submitted by readers. The December 1937 issue of Popular Mechanics magazine published this collection of "hints" which included a homemade filter for blocking interference from appliances with electrically noisy motors (arcing from armature brushes) and a means of isolating a possibly hot chassis from the power source. Poor design and the lack of polarization on AC plugs meant there was a 50-50 chance the metal chassis would be "hot." The plan for a wind-powered generator could easily be something seen in a contemporary magazine. Back in the day, many rural locations had no commercial electric service and relied on wind and water turbines to provide power to household and farm implements.

Hints for Radio Experimenters

Homemade noise filter for power line eliminates interference caused by refrigerator or other apparatus operated on same line as receiver.

Insulating bushing easily made from paper strip and Bakelite blocks. Dip in paraffin before assembling on metal chassis.

Below, multiple crystal holder for transmitter; four separate crystals selected by built-in switch. Right, spring suspension quiets battery charger; optional method, put charger on piece of asbestos placed on felt pad.

Sketch below shows suggestions for installing a "supercharger" or wind-driven battery charger to obtain unobstructed sweep of wind.

Below, simple method of taping the end of a wire to prevent shorts. Left, acoustical padding arrangement improves low-frequency response of older console cabinets.

Posted November 16, 2023