• Country
• United States of America (USA)

• Manufacturer / Brand
• Electrical Research Laboratories Inc. (Erla); Chicago, Illinois

• Year
• 1930

• Category
• Broadcast Receiver - or past WW2 Tuner

• Radiomuseum.org ID
• 38110

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

• Number of Tubes
• 7

• Valves / Tubes
• 32 32 32 30 30 71A 71A

• Main principle
• Special principle (see notes); Screengrid 1926-1935

• Tuned circuits
• 4 AM circuit(s)

• Wave bands
• Broadcast only (MW).

• Power type and voltage
• Line / Batteries (any type) / 32 & 135. Volt

• Loudspeaker
• Electro Magnetic Dynamic LS (moving-coil with field excitation coil)

• Material
• Wooden case

• from Radiomuseum.org
• Model: 75 Ch= 231 [C 175$] - Electrical Research

• Shape
• Console with any shape - in general

• Notes

• Farm radio, requires 32 V and an additional 135 V dry battery (or eliminator).
  One dial (primary tuning control knob); 4-gang condenser; push-pull af output stage.
  Dated 1929 since "Grinder" and "Radio Coll. Guide" say 1928, while schematic as well as the "Radio Set Socket Layout" show 1930.

  According to Tyne, page 329, the tube UX230 (30) and the tube UX232 (32) arrived in 1930. Therefore this model can not be from before or had another first tube line-up.

• Price in first year of sale
• 175.00 $

• External source of data
• Ernst Erb

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

• Circuit diagram reference
• Rider's Perpetual, Volume 2 = 1932 (Models 1931/1932)

• Mentioned in
• The Radio Collector's Directory and Price Guide 1921 - 1965

• Literature/Schematics (1)
• Radio Set Socket Layout 1921 to 1935, RCA

• Other Models

• Here you find 133 models, 47 with images and 61 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Electrical Research Laboratories Inc. (Erla); Chicago, Illinois