A Simple Wireless Detector
This Neat Wireless Detector was Made of Materials Easily Gathered in the Boy’s Workshop
A cheap and serviceable wireless detector was made from odds and ends such as any amateur can obtain. The base was made of wood, saturated in paraffin. The mineral cup is a brass cap from a cartridge fuse. The upright was made of a piece of copper, ¹⁄₂ by 4¹⁄₂ in. long, and is fastened to the base by an old-battery binding post. The spring which supports the cat whisker is made of a strip of copper, ¹⁄₃₂ in. by ³⁄₁₆ in. wide. The cat whisker is soldered to the spring, and the spring is bolted to the upright. The setscrew, which regulates the pressure of the cat whisker upon the mineral, works in a nut, soldered over a hole in the top of the upright. The cat whisker is made of No. 22 gauge bare copper wire. The connection between the cup and the battery binding post, at the front edge, is made on the under side of the base.—Charles Brinkmann, Chicago, Ill.