• Country
• United States of America (USA)

• Manufacturer / Brand
• Clapp-Eastham Co.; Cambridge, MA

• Year
• 1920

• Category
• Radio module pre 1926 (not a part, not a key)

• Radiomuseum.org ID
• 35306

• • Brand: Radak

Click on the schematic thumbnail to request the schematic as a free document.

• Main principle
• Tuner pre 1926 (not a wave trap)

• Wave bands
• Broadcast only (MW).

• Power type and voltage
• No Power needed

• Loudspeaker
• - - No sound reproduction output.

• Material
• Various materials

• from Radiomuseum.org
• Model: Regenerative Receiver ZRF - Clapp-Eastham Co.; Cambridge,

• Shape
• Chassis only or for «building in»

• Dimensions (WHD)
• 14.75 x 5.5 x 5 inch / 375 x 140 x 127 mm

• Notes
• This set is named "Receiver" although it is in fact a tuner without demodulation. It was typical of the various models of the popular early 1920's three circuit tuner. This early set consisted of a vario-coupler in the antennae circuit, a variometer connected in the grid circuit and a variometer connected in the plate circuit together with a grid condensor and a grid leak and covered the 175-600 Meters wavelength. Matched with some type of detector panel such as the Clapp-Eastham ZRD the user then had a complete regenerative radio.

• Price in first year of sale
• 38.00 $

• External source of data
• Ernst Erb

• Source of data
• Radio Collector`s Guide 1921-1932

• Mentioned in
• Radio Manufacturers of the 1920s, Vol 1

• Other Models

• Here you find 130 models, 107 with images and 3 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Clapp-Eastham Co.; Cambridge, MA