• Country
• Japan

• Manufacturer / Brand
• Panasonic, Matsushita, National ナショナル (also tubes); Osaka

• Year
• 1958 ??

• Category
• Broadcast Receiver - or past WW2 Tuner

• Radiomuseum.org ID
• 193581

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

• Number of Transistors
• 8

• Semiconductors
• MC101 MC102 or. MC103 OC45 OC45 OC71 OC71 OC76 OC76 OA70 OA70 MA23

• Main principle
• Superheterodyne (common); ZF/IF 455 kHz; 3 AF stage(s)

• Tuned circuits
• 6 AM circuit(s)

• Wave bands
• Broadcast and Short Wave (SW).

• Power type and voltage
• Dry Batteries / 6 x 1,5 Volt

• Loudspeaker
• Permanent Magnet Dynamic (PDyn) Loudspeaker (moving coil) / Ø 12 cm = 4.7 inch

• Material
• Plastics (no bakelite or catalin)

• from Radiomuseum.org
• Model: National 2 Band 8 Transistor DB-421 HJ - Panasonic, Matsushita,

• Shape
• Tablemodel, with any shape - general.

• Notes

• The schematic drawing (ID=956435, between the photos) shows another transistor for the RF mixer: OC44 instead of MC101.

  It is also a general schematic for both DB-421 subtypes "H" and "J" while subtype "HJ" is mentioned on the lower right side but doesn't actually exist since it is mentioned nowhere else on the schematic. The difference between the 2 subtypes is the value of a few capacitors. The fact that "HJ" is mentioned as such on the schematic justifies this model.

  Frequency Range:

  • MW: 540 - 1630 kHz; this band has also a "local" setting for strong signals.
  • SW (subtype "H"): 3.8 - 12 MHz.
  • SW (subtype "J"): 7 - 16 MHz.

• Author
• Model page created by Keith Staines. See "Data change" for further contributors.

• Other Models

• Here you find 3049 models, 2826 with images and 632 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Panasonic, Matsushita, National ナショナル (also tubes); Osaka