NOTE: If you are interested in these subjects, you might wish to join the Xtal Set Society. They publish an interesting newsletter concerned with detectors and the building of crystal sets. Contact Phil Anderson, 789 N 1500 Rd., Lawrence, KS 66049-9194, fax (913)-842-1227, or visit their web site:

RPR31: Goldsmith Publishing Co., Radio: How To Make and Operate
Cleveland 1922 Goldsmith. 4 x 5" booklet. 60 pages reprinted as a brochure. Complete instructions on how to build and wire two crystal sets (one with a coil with selector switches, the other with a coil with a slider contact.) Much other material on antennas, components, parts lists, etc. $4.50

RPR26: National Radio Institute, Radio Reception and the Crystal Detector
Washington DC, NRI, 1927. Lesson 9 of "Complete Course in Practical Radio" 29 pages. Reprint of complete lesson brochure w/paper cover. Detailed description of how to build a simple crystal receiver plus notes in using vario-coupler and vario-meter. 6 x 9" brochure. $4.00

RPR25: Verrill, A. Hyatt, Two Selections
1st Selection: pages 80-119 from Radio For Amateurs (NY, Bodd, Mead & Co., 1922) Chapters 8 and 9 cover How to Make Various Instruments (Coils, Variometers, condensers and crystal detectors) and Chapter IX, Simple Receiving Sets (Crystal Sets and Regenerative Tube Receivers).
2nd Selection: pp 74 to 98 from The Home Radio: How To Make and Use It. Chapter XIV covers Inductances and Tuning Coils, Ch. XV covers Vario-Couplers and Variometers; Ch. XVI covers Receiving Sets and Ch. XVII & XVIII cover Crystal sets. w/illus. Total: 40pp +. 2 to 1. Both items $5.00

RPR39: Walter, L.H., Magnetic Detectors of Electric Waves.
From Technics, July, 1905. Pages 127 to 131. Part I only of a two part article, but complete in itself. Describes and discusses several different kinds of magnetic detectors, including Rutherford, Wilson, Marconi, Shoemaker, Walter-Ewing, and Fessenden. 5 pages, 2 to 1. $2.00

RPR12: Wireless Detectors, Various Articles.
From Mechanics and Electricians, Wireless Detectors 10 articles on wireless detectors, July 1907 to June 1911. 23 pages total. (2 to 1) Contains all articles on wireless detectors published during that period. Includes articles by A. P. Morgan, W. C. Getz and Edward Gage. Includes Magnetic, Electrolytic, Tantalum, and Perikon detectors. Also included: "Oddities in Detectors" by George Worts from Popular Electricity Magazine Oct. 1910. 4 pages (1 to 1) Both items (27 pages) $3.50

RPR33: (Unknown), Wireless Signals Registered by Frog Muscles.
From Popular Electricty Magazine, January, 1911, pages 961-962. Actually describes how frog legs can be used to detect wireless signals! With diagrams of the apparatus. 2 pages, 2 to 1. Free with any order. (Be sure to specify if wanted)

RPRXTAL: Combination offer: RPR31, RPR26, RPR25, RPR39, RPR12 and RPR33. All 6 items $16. (plus postage).