The plans for this British crystal set appeared 90 years ago in the December 17, 1927 issue of Amateur Wireless.

The set was billed as an ideal Christmas gift for someone living close to a BBC station. “A receiver such as this is inexpensive to build and would make an admirable Christmas gift to someone who lives near a B.B.C. station and has facilities for the erection of a reasonably efficient aerial-earth system.”

According to the article, if the set was equipped with a good aerial and earth, it would work two pairs of headphones with good volume, at a range of up to 12 miles from a main BBC station, or about half that distance from a relay station. The set was simple to operate, since it used a “permanent” crystal detector.

The article used quotation marks, since apparently the detector (available from either R.I. and Varley, or the Jewel Pen Company) was capable of an initial adjustment. “When testing on actual reception, carefully adjust the crystal detector until loudest results are obtained, and then leave well alone, as far as the detector is concerned.”