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SCR-508

WW2-era US Army radio

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The SCR-508 radio was a mobile Signal Corps Radio used by the U.S. Army during World War II, for short range ground communications. The SCR-508 series radio represented the Army's commitment to both FM and crystal tuning, and was used extensively by armor and mechanized units. The turret bustle of late series light and medium tanks was designed around this radio.

01Use

The SCR-508 series was standardized on 22 July 1941, and used by armored forces for command and control of tank units. It replaced the earlier SCR-293 and SCR-245 and was used primarily in the M5 Stuart light tanks as well as the M4 Sherman medium tanks. It also provided the intercom system to all crew stations. It provided voice communications between tanks and other vehicles/units equipped with FM radios (such as the SCR-510 and others) operating in the same frequency range. One of 10 channels could be selected by the operator, a total of 80 channels were available for use at 100 kHz channel spacing. Channels were referred to by a numerical identifier. For example, 27.1 MHz was "channel 271", 25.0 MHz was "channel 250" and so on. It was replaced by the AN/VRC-8 series radios.

02Components

  • BC-604 transmitter (FM, CW/voice), 10 crystal controlled channels covering 20.0 to 27.9 MHz (14.99 to 10.75 m), 25 watts, range 7 mi (11 km)
    • DM-35 dynamotor (12 Volt input) or
    • DM-37 dynamotor (24 Volt)
  • BC-603 receiver (2 for 508 set)
    • DM-34 dynamotor (12 volt input) or
    • DM-36 dynamotor (24 volt)
  • FT-237 mount or rack
  • CH-74 cabinet for use in open command vehicles (FT-284 Legs)
  • MP-52 mast base for CH-74
  • MP-48 antenna base, and 9 ft (2.7 m) whip antenna
  • CH-264 chest for parts and accessories (could be slid into mount in place of receiver)
  • T-17 microphone
  • HS-30 headset
  • RM-29 telephone patch set
  • BC-606 intercom box, at crew stations
  • I-208 signal generator (TM 11-317)

03Variants

Different combinations of components could be arranged in the mounts.

  • SCR-528 transmitter and single receiver
  • SCR-538 Receiver and BC-605 Amplifier (for intercom)
  • AN/VRC-5 Separately mounted transmitter and receiver
    • FT-508 mount (transmitter)
    • FT-345 mount (receiver)

The Artillery branch used the same radios mirroring the SCR-508 series but with a different frequency range

  • SCR-608
    • BC-684 transmitter 27.0 to 38.9 MHz (11.10 to 7.71 m) at 35 watts, for 15 mi (24 km)
    • BC-683 receiver
  • SCR-628

04General references

  • TM 11-487 Electrical Communications Equipment
  • TM 11-600 SCR-508 Operator
  • TM 11-620 SCR-608 operators
  • Radio to free Europe
Watch videos about SCR-508Explainers and documentaries on YouTube (opens in a new tab)

Sources and credits

This article is adapted from the Wikipedia article SCR-508, written by its contributors and licensed under CC BY-SA 4.0. Fathomly has changed the layout, removed citation markers, navigation and maintenance notices, and adjusted punctuation. This adapted version is shared under the same license. For references, see the original article.

Images, from Wikimedia Commons:

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