BC-684-(*) part of SCR-608, SCR-628

MILITARY U.S. (different makers for same model)

  • Year
  • 1944 ?
  • Category
  • Commercial Transmitter (TX not Transceiver)
  • Radiomuseum.org ID
  • 88567

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

 Technical Specifications

  • Number of Tubes
  • 8
  • Wave bands
  • Wave Bands given in the notes.
  • Power type and voltage
  • Storage Battery for all (e.g. for car radios and amateur radios) / 12 / 24 Volt
  • Loudspeaker
  • - - No sound reproduction output.
  • Material
  • Metal case
  • from Radiomuseum.org
  • Model: BC-684- [part of SCR-608, SCR-628] - MILITARY U.S. different makers
  • Shape
  • Tablemodel, low profile (big size).
  • Dimensions (WHD)
  • 18 x 9.1 x 11.5 inch / 457 x 231 x 292 mm
  • Notes
  • VHF-Transmitter BC-684: Frequency range 27–38,9 MHz, 10 crystal controlled channel presets, NBFM, output power 20 W.

    Under the lid left next to the controls, the crystals for the ten pretuned channels are plugged in; the other cover in left upper corner of the fronat panel gives access to the crystal box BX-40 with all channel crystals. Sets with a complete crystal box and the original dynamotor still in place will give a better collectors price.

    Part of field artillery radio sets SCR-608 and SCR-628 along with one or two BC-683 receivers. Powered via dynamotors from vehicle battery 12 V (DM-35) or 24 V (DM-37).

    • Variant: BC-648-A: no internal intercom function (no switch below pilat lamp)
    • Variant: BC-684-B: internal intercom funcion for armed vehicles and tank (can be recognized by an additional switch below the pilot lamp right below the meter)
    • in Switzerland found as SE-408 / FIX; french frontplatte labels due to french license production
  • Net weight (2.2 lb = 1 kg)
  • 30.1 kg / 66 lb 4.8 oz (66.3 lb)
  • Source of data
  • -- Original-techn. papers.
  • Mentioned in
  • -- Original-techn. papers. (TM 11-620)
  • Literature/Schematics (1)
  • -- Original-techn. papers. (TM 11-4037 Repair Instructions)
  • Author
  • Model page created by Martin Bösch. See "Data change" for further contributors.

 Collections | Museums | Literature


The model is part of the collections of the following members.


Forum contributions about this model: MILITARY U.S.: BC-684-

Threads: 1 | Posts: 1

Hallo, I scanned the Service Manual for the SCR-608 / 628 radio sets including the BC-684A transmitter, it can be found for download at
or on my personal website
Hope that helps Martin Boesch

Martin Bösch, 06.Jan.06

Weitere Posts (1) zu diesem Thema.