• Country
• United States of America (USA)

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

• Year
• 1958

• Category
• Broadcast Receiver - or past WW2 Tuner

• Radiomuseum.org ID
• 172191

• • alternative name: Chicago Radio Lab

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

• Number of Transistors
• 8

• Semiconductors
• 121-63 or. 2N544 or. 121-78 121-62 or. 2N411 121-65 or. 2N409 121-66 or. 2N409 or. 121-73 121-66 or. 2N409 or. 121-74 121-64 or. 2N407 121-61 or. 2N407 121-61 or. 2N407

• Main principle
• Superhet with RF-stage; ZF/IF 455 kHz; 2 AF stage(s)

• Tuned circuits
• 5 AM circuit(s)

• Wave bands
• Broadcast only (MW).

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

• Loudspeaker
• Permanent Magnet Dynamic (PDyn) Loudspeaker (moving coil) / Ø 2.75 inch = 7 cm

• Material
• Plastics (no bakelite or catalin)

• from Radiomuseum.org
• Model: Royal 500RD Ch= 8AT40Z2 - Zenith Radio Corp.; Chicago,

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

• Notes

• The Zenith Royal 500D family has two chassis, four transistor label colors, and two cabinet styles. The four chassis, in chronological order, are summarized in the following table. Note that only about 2,000 Type 1 chassis were made.

  Type	Chassis	Dot/ Label Color	RF	Mix	Osc	1st IF	2nd IF	Det	Drvr	Out x2	Man
  1	8AT40Z2	Black	121-63 2N544	121-62 2N411	121-65 2N409	121-66 2N409	121-66 2N409	103-19 1N87G	121-64 2N407	121-61 2N407	RCA
  2	8AT40Z2	Red	""	""	""	121-73	121-74	""	""	""	""
  3	8AT40Z2	Green	or -78	''	''	''	''	''	''	''	''
  4	8AT40	Blue	121-101 2N544	121-103 2N411	121-102 2N409	121-104 2N409	121-105 2N409	""	121-106 2N407	121-107 2N407	Syl

  The earlier first cabinet style had "LONG DISTANCE" stamped below the engraved "ZENITH" brand on the front. Initially, the colors were black and maroon. Later colors added were pink, tan, and white.

  The later second cabinet style added a black "500D" under the Zenith emblem (smaller than the first emblem) on the metal faceplate. A new inverted cone speaker was introduced, with the speaker grill also pushed out to accommodate the inverted cone. Not all 500D radios used the new speaker. The colors were black, maroon, and white.

  The earlier cabinet was used with Types 1, 2, and 3 chassis. The later cabinet was used with Types 2, 3, and 4 chassis.

  The five Royal 500D models are 500RD, 500WD, 500YD, 500D Ch= 8AT40Z2, and 500D Ch= 8AT40.

  Umfassende Beschreibung in Deutsch.

• Mentioned in
• Zenith Transistor Radios (pages 23-24.)

• Literature/Schematics (1)
• Photofact Folder, Howard W. SAMS (Set 422, Folder 17, Nov. 1958.)

• Literature/Schematics (2)
• -- Original-techn. papers. (Antique Radio Magazine n.61, June-July 2004, page 53 (Ita/Eng). Free at Aldo Andreani's website.)

• Literature/Schematics (3)
• -- Original-techn. papers. (Zenith Royal 500 Transistor Radios "Owl Eyes" booklet, Eldon A. Horton, pages 1-20.)

Radio a transistor tascabili americane: Zenith Royal 500 “Owl Eyes” (Per cortesia di L.Salvatore/ARM)

3327 KB

• Documents regarding this model

• Author
• Model page created by Egon Penker. See "Data change" for further contributors.

• Other Models

• Here you find 4517 models, 4108 with images and 3646 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Zenith Radio Corp.; Chicago, IL