• Country
• United States of America (USA)

• Manufacturer / Brand
• Radio Shack (Tandy, Realistic, Micronta); USA

• Year
• 1969 ?

• Category
• Kit (Parts plus instruction) or building instructions only

• Radiomuseum.org ID
• 222954

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

• Number of Transistors
• 2

• Semiconductors
• 2SB54 2SB54

• Main principle
• Crystal or Solid State Detector with Amplifer; 2 AF stage(s)

• Tuned circuits
• 1 AM circuit(s)

• Wave bands
• Broadcast only (MW).

• Power type and voltage
• Dry Batteries / 9 Volt

• Loudspeaker
• - Is a Headphone or Earphone

• Material
• Plastics (no bakelite or catalin)

• from Radiomuseum.org
• Model: Science Fair Two Transistor Radio in P-box 28-102 - Radio Shack Tandy, Realistic,

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

• Dimensions (WHD)
• 120 x 95 x 50 mm / 4.7 x 3.7 x 2 inch

• Notes

• Radio Shack produced a number of inexpensive kits labeled Science Fair "P-box" kits.

  From the instruction pamphlet for model 28-102:  The circuit is a basic detector/ampliifer. The proper frequency is selected by the antenna coil and capacitor C2.  The audio signal is removed from the radio signal by diode detector D1.  The audio signal is amplified by transistor Q1 and again by transistor Q2.  The signal is then loud enough to be heard clearly through the earphone.

   

• Net weight (2.2 lb = 1 kg)
• 1 lb (1 lb 0 oz) / 0.454 kg

• Price in first year of sale
• 3.95 US$

• Mentioned in
• Radio Shack catalog 1969, p 127

• Literature/Schematics (1)
• Kit 28-102 pamphlet

• Author
• Model page created by Bill Miller. See "Data change" for further contributors.

• Other Models

• Here you find 1299 models, 1181 with images and 117 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Radio Shack (Tandy, Realistic, Micronta); USA