• Country
• United States of America (USA)

• Manufacturer / Brand
• MILITARY U.S. (different makers for same model)

• Year
• 1940

• Category
• Military transmitter

• Radiomuseum.org ID
• 312365

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

• Number of Tubes
• 4

• Valves / Tubes
• 1626 1625 1625 1629

• Main principle
• Transmitter

• Wave bands
• Short Wave (SW only)

• Power type and voltage
• Storage Battery for all (e.g. for car radios and amateur radios) / 28 Volt

• Loudspeaker
• - - No sound reproduction output.

• Power out
• 40 W (unknown quality)

• Material
• Metal case

• from Radiomuseum.org
• Model: Radio Transmitter BC-457- - MILITARY U.S. different makers

• Shape
• Boatanchor (heavy military or commercial set >20 kg).

• Dimensions (WHD)
• 184 x 223 x 382 mm / 7.2 x 8.8 x 15 inch

• Notes

• Aircraft Transmitter BC-457-A: part of Radio Set SCR-274-N:

  Transmitter CW, MCW, AM; frequency range 4.0 - 5.3 MHz, 4.6 MHz crystal for dial alignment.

  Needs modulator unit BC-456-A for plate voltage supply and as modulator stage; cannot be operated as standalone transmitter.

  Remote control by radio control box BC-451-A.

  Used for short range aircraft communications between different aircraft and between aircraft and control tower; part of radio installation in U.S. aircraft like B-17, B-24.

  Technically very similar to JAN T-20/ARC-5, which was the joint Army - Navy successor set.

• Net weight (2.2 lb = 1 kg)
• 4.1 kg / 9 lb 0.5 oz (9.031 lb)

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

• Author
• Model page created by Martin Bösch. See "Data change" for further contributors.

• Other Models

• Here you find 398 models, 350 with images and 210 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from MILITARY U.S. (different makers for same model)