• Country
• Japan

• Manufacturer / Brand
• Sony Corporation; Tokyo

• Year
• 1986 ?

• Category
• Sound/Video Recorder and/or Player

• Radiomuseum.org ID
• 147491

• Number of Transistors
• Semiconductors present.

• Semiconductors

• Main principle
• Audio-Amplification

• Wave bands
• - without

• Details
• Cassette-Recorder or -Player

• Power type and voltage
• Dry Batteries / 2 x 1,5 Volt

• Loudspeaker
• - For headphones or amp.

• Material
• Various materials

• from Radiomuseum.org
• Model: Walkman Stereo Cassette Player WM31 - Sony Corporation; Tokyo

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

• Dimensions (WHD)
• 120 x 88 x 33.5 mm / 4.7 x 3.5 x 1.3 inch

• Notes
• Power Output 15+15 mW.
  Frequency response 40-14000 Hz (CrO2/Metal),
  40-14000 Hz (Normal). 4-track 2-channel stereo.

• Net weight (2.2 lb = 1 kg)
• 0.2 kg / 0 lb 7 oz (0.441 lb)

• Source of data
• - - Manufacturers Literature

• Mentioned in
• -- Original-techn. papers.

• Author
• Model page created by Eero Ukkola. See "Data change" for further contributors.

• Other Models

• Here you find 3960 models, 3820 with images and 954 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Sony Corporation; Tokyo