• Country
• United States of America (USA)

• Manufacturer / Brand
• Zenith Radio Corp.; Chicago, IL

• Year
• 1961

• Category
• Broadcast Receiver - or past WW2 Tuner

• Radiomuseum.org ID
• 73988

• • alternative name: Chicago Radio Lab

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

• Number of Transistors
• 7

• Semiconductors

• Main principle
• Superheterodyne (common); ZF/IF 455 kHz

• Wave bands
• Broadcast only (MW).

• Power type and voltage
• Dry Batteries / 4 x AA 1.5 Volt

• Loudspeaker
• Permanent Magnet Dynamic (PDyn) Loudspeaker (moving coil) - elliptical

• Power out
• 0.1 W (unknown quality)

• Material
• Plastics (no bakelite or catalin)

• from Radiomuseum.org
• Model: Royal 400 Pocket Radio 7GT40Z2 - Zenith Radio Corp.; Chicago,

• Shape
• Very small Portable or Pocket-Set (Handheld) < 8 inch.

• Dimensions (WHD)
• 87 x 150 x 44 mm / 3.4 x 5.9 x 1.7 inch

• Notes

• available in: ebony, white, two-toned brown, two-toned green, color type extensions are (400) F/J/W/Y;

  Civil Defense marks on station dial.  Transistors are mounted on 'plug-in' sockets, a contrivance of Zenith to allow failing transistors to be easily replaced.  Early Zenith transistors were manufactured by several companies causing Zenith some concern about dependability of the transistors and customer satisfaction.  Plug-in sockets were soon discontinued as the transistors proved to be dependable.

• Price in first year of sale
• 40.00 $

• Circuit diagram reference
• Beitman Radio Diagrams Vol. 22, 1962

• Mentioned in
• Zenith Transistor Radios

• Literature/Schematics (1)
• Photofact Folder, Howard W. SAMS (Set 613 Folder 16 1-1963)

• Literature/Schematics (2)
• Photofact TSM Transistor Radio Series SAMS (TSM-23 (March, 1963))

• Author
• Model page created by Konrad Birkner † 12.08.2014. See "Data change" for further contributors.

• Other Models

• Here you find 4505 models, 4101 with images and 3631 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Zenith Radio Corp.; Chicago, IL