Monthly Archives: March 2018

1941 Lew Bonn Company Catalog

LewBonnCatalog011One of our readers recently sent us the catalog shown here. The full catalog is 168 pages, and we’ll periodically post a few pages.

The catalog is from a distributor I had never heard of, Lew Bonn Co., 1211 LaSalle Avenue, Minneapolis. It doesn’t seem to have a date, but it appears to be from early 1941. The book listing includes the “new” 1941 edition of the Radio Handbook, and it also includes the Rider Manuals up through volume 11, covering 1940-41 radios. It also notes that the 12th volume will be available soon.

The catalog also contains a full selection of amateur gear, indicating that the catalog came out before Pearl Harbor. Therefore, I conclude that the catalog dates to early 1941.

Included here are the first twelve pages of the 168 page catalog.  In the coming weeks, we’ll add more pages until it’s completely available.  You can click on any of the images below to see a larger version.

Today, we present the index (pages 1-3), some of the specials to be found in the Bargain Basement (pages 4-7), electrical appliances (pages 8-10), car radios (page 11), and power supplies and inverters (page 12).

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1938 Miniature UHF Transceiver

1938MarPS1938MarPS1Eighty years ago this month, the March 1938 issue of Popular Science carried the plans for this transceiver, which it billed as the world’s smallest two-way radio. Weighing less than ten ounces, the set could be carried in a coat pocket. The set shown here was for the 3/4 meter band, but could also be built for the 1-1/2 meter band. The heart of the circuit was a 955 acorn tube.

A DPDT switch was used to switch 1938MarPS2from transmit to receive. In the transmit position, the circuit was an efficient oscillator, and in receive, a grid leak and condenser were added to the circuit to produce a sensitive receiver.

The external batteries were acually larger than the radio. Two 3-volt flashlight batteries were used for the filaments, with a 45 volt battery providing the B+.

In order to make sure the radio was operating within the amateur band, the article described a simple wave meter, consisting of a flat U-shaped loop of No. 12 wire hooked to a galvanometer. The transmitter was held close to the loop and moved along until the highest current rating was shown. The transmitter wavelength was equal to the distance along the wire to the meter.

The construction article reminded readers that an amateur license was necessary to use the transmitter. But for those considering trying for the license in the near future, the construction of the set would teach many of the radio fundamentals that would be on the test.

The circuit here is similar to this WERS transceiver shown here previously. In case you’re wondering, the 955 tubes do seem to be readily available on eBay.

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1943 Dymaxion Map

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Fuller and the Dymaxion map.

Fuller and the Dymaxion map.

Seventy-five years ago today, the pages of Life Magazine, March 1, 1943, included a craft project, in the form of a Dymaxion map of the world. A flat map of the round earth is always distorted, in either scale, direction, or shape. For example, the familiar Mercator projection accurately shows direction, but scale is greatly distorted close to the poles, which explains why Greenland looks much larger than it really is.

Wikipedia animation.

The Dymaxion map, designed by R. Buckmisnter Fuller, seeks to compromise to make all of these distortions as minimal as possible. It is a cube with the corners cut off, and is formed from six squares and eight triangles.  The transformation from a round globe to a flat map is shown in the animation at right.

The magazine contained all of these sections, some of which are shown above, with instructions for pasting them to cardboard and assembling them. When assembled, they could be laid out flat in various configurations, or put together completely as a squared-off globe.  For those wishing to duplicate the 1943 globe, it would be an easy process to print the pages on cardstock and assemble them following the directions.  (You can download the magazine at  this link,)

An interesting science fair project could be made comparing a globe, a Mercator projection, and the Dymaxion projection.