Screen Grid Six SM-720 Kit

Silver - Marshall; Chicago, IL

Data
Forum
Pictures
Collections

  • Year
  • 1928/1929
  • Category
  • Kit (Parts plus instruction) or building instructions only
  • Radiomuseum.org ID
  • 57930

 Technical Specifications

  • Number of Tubes
  • 6
  • Main principle
  • TRF (Tuned-Radio-Frequency but use of regeneration unknown); 2 AF stage(s); Screengrid 1926-1935
  • Wave bands
  • Broadcast only (MW).
  • Power type and voltage
  • Powered by external power supply or a main unit.
  • Loudspeaker
  • - This model requires external speaker(s).
  • Material
  • Metal case
  • from Radiomuseum.org
  • Model: Screen Grid Six SM-720 [Kit] - Silver - Marshall; Chicago, IL
  • Shape
  • Chassis only or for «building in»
  • Notes
  • Two dials (primary tuning control knobs) The 720 receiver consists of three stages of radio frequency amplification, using screen-grid tubes, followed by a super-sensitive detector, and two stages of Clough high-gain audio frequency amplification, with power output tube- 112, 171, 210 or 250 type being optional. It may be operated from batteries or the SM-670B or 675 ABC Reservoir B Power Supply, in combination with any good A power unit, makes the ideal power plant for this receiver.
  • Price in first year of sale
  • 72.50 $
  • External source of data
  • Ernst Erb
  • Literature/Schematics (1)
  • Walter Ashe Radio Co. catalogue for season 1928-1929
  • Literature/Schematics (4)
  • August 1928 Silver-Marshall catalog page 4-5

 Collections | Museums | Literature

Collections

The model Screen Grid Six is part of the collections of the following members.

 Forum