• Country
• United States of America (USA)

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

• Year
• 1923

• Category
• Broadcast Receiver - or past WW2 Tuner

• Radiomuseum.org ID
• 35299

• • Brand: Radak

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

• Number of Tubes
• 1

• Valves / Tubes
• WD12

• Main principle
• TRF with regeneration

• Tuned circuits
• 1 AM circuit(s)

• Power type and voltage
• Dry Batteries

• Loudspeaker
• - For headphones or amp.

• Material
• Wooden case

• from Radiomuseum.org
• Model: Radak R4 [.] - Clapp-Eastham Co.; Cambridge,

• Shape
• Tablemodel, Box - most often with Lid (NOT slant panel).

• Dimensions (WHD)
• 8 x 9.5 x 6 inch / 203 x 241 x 152 mm

• Notes
• Two dials (primary tuning control knobs); matching 2 stage amplifier A4.

• Net weight (2.2 lb = 1 kg)
• 2.7 kg / 5 lb 15.2 oz (5.947 lb)

• Price in first year of sale
• 25.00 $

• External source of data
• Ernst Erb

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

• Mentioned in
• Collector's Guide to Antique Radios (6th edition)

• Literature/Schematics (1)
• Radio Manufacturers of the 1920s, Vol 1 (page 106)

• 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