A hundred years ago this month, the April 1923 issue of Radio Age showed how to put together this handsome crystal set. The plans were actually courtesy of the U.S. Bureau of Standards, and the construction article was a reprint of a government pamphlet. The set was an upgrade from an earlier Bureau of Standards model, and featured greater selectivity. The total cost was said to be about $15.00. If the earlier set had already been built, the additional components would cost about $5.00.

The article describe the construction of the variable couple, the inner coil of which slid on a wooden base into the larger. However, it also noted that a commercially built unit could be used.

Readers considering duplicating this circuit will be able to find many of the required parts on our crystal sets parts page.