• Country
• United States of America (USA)

• Manufacturer / Brand
• DeForest Radio Telephone & Telegraph Co. (De Forest); New York

• Year
• 1922

• Category
• Broadcast Receiver - or past WW2 Tuner

• Radiomuseum.org ID
• 37085

• • alternative name: Lee De Forest Mfg.

• Number of Tubes
• 3

• Valves / Tubes
• DV6 DV6 DV6

• Main principle
• Special principle (see notes); 2 AF stage(s)

• Wave bands
• Broadcast only (MW).

• Power type and voltage
• Storage and/or dry batteries

• Loudspeaker
• - This model requires external speaker(s).

• Material
• Wooden case

• from Radiomuseum.org
• Model: Reflex Radiophone D7 - DeForest Radio Telephone &

• Shape
• Tablemodel, high profile (upright - NOT Cathedral nor decorative).

• Dimensions (WHD)
• 10 x 10 x 8 inch / 254 x 254 x 203 mm

• Notes
• Two dials (primary tuning control knobs) Introduced in December of 1922 the DeForest D7 existed for only a couple of months when in February 1923 it became the D7-A. The D7 has a wavelength range of 200-550 meters, although adjustments can be made in the set which will enable it to receive longer wavelengths. The circuit is a combination of radio and audio frequency. The signals are first passed through the three tubes at radio frequency. The amplified radio frequency signal is then rectified in a crystal detector. The rectified signal is then reflexed through the last two tubes at audio frequency, and the signal is conducted to the head-phones or the loud speaker. The result is five stages of amplification with three tubes.

• Price in first year of sale
• 175.00 $

• External source of data
• Ernst Erb

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

• Mentioned in
• Collector's Guide to Antique Radios 4. Edition

• Literature/Schematics (1)
• - - Manufacturers Literature

• Literature/Schematics (4)
• Deforest Radio Equipment Catalog L page 3

• Other Models

• Here you find 158 models, 132 with images and 16 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from DeForest Radio Telephone & Telegraph Co. (De Forest); New York