• Country
• United States of America (USA)

• Manufacturer / Brand
• Madison Industries Products Development Co.; Lawrence, IN

• Year
• 1957 ?

• Category
• Broadcast Receiver - or past WW2 Tuner

• Radiomuseum.org ID
• 338484

• Number of Transistors
• 4

• Semiconductors

• Main principle
• Superheterodyne (common); ZF/IF 455 kHz; 1 AF stage(s)

• Tuned circuits
• 5 AM circuit(s)

• Wave bands
• Broadcast only (MW).

• Power type and voltage
• Dry Batteries / 1 x 9 Volt

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

• Material
• Plastics (no bakelite or catalin)

• from Radiomuseum.org
• Model: Mantola All Transistor M-4D - Madison Industries Products

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

• Dimensions (WHD)
• 3 x 5 x 1.25 inch / 76 x 127 x 32 mm

• Notes

• Same circuit as the Regency TR4.  Sold by B.F. Goodrich stores.

• Mentioned in
• The AWA Review, Vol. 17, 2004, pgs. 21-23 & 25, The Regency TR-1: 50 Years Later by Paul R. Farmer

• Literature/Schematics (1)
• Collector's Guide To TrR1 Bunis trans.94 (1994 pg. 116; 1996 pg. 153 with photo.)

• Literature/Schematics (2)
• Photofact Folder, Howard W. SAMS (Set 381, Folder 12, March 1958)

• Author
• Model page created by Aldo Sito. See "Data change" for further contributors.

• Other Models

• Here you find 1 models, 1 with images and 0 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Madison Industries Products Development Co.; Lawrence, IN