via HACKADAY: Crystal Radio Kit from the 1970s

If you read the December 1970 issue of Mechanix Illustrated, you’d be treated to [Len Buckwalter]’s crystal radio build. He called out Modern Radio Labs as the supplier for parts. That company, run by [Elmer Osterhoudt], got so many inquiries that he produced a kit, the #74 crystal set. [Michael Simpson] found an unopened kit on eBay and — after a bidding war, took possession of the kit. The kit looked totally untouched. The crystal detector was still in the box, and there were period-appropriate newspaper wrappings.

The kit itself isn’t that remarkable, but it is a classic. An oatmeal box serves as a coil form. There’s a capacitor, a crystal detector, and headphones. The original cost of the parts was $7, but we imagine the eBay auction exceeded that by a large amount.

If the name [Len Buckwalter] sounds familiar, he was quite prolific in magazines like Electronics Illustrated and also wrote several books about transistors. [Michael] also shows off his innovative coil winder made from plastic cups and a coat hanger.