Master time control clock, Cape Elizabeth, ca. 1950

Contributed by Museum at Portland Head


The IBM Electric Self Winding Time Control Clock was used at the Radiobeacon Station.

This one may have been used at the station at Cape Elizabeth Light (Two Lights). Its time was checked at the beginning of every watch or every six hours with the Bureau of Standards Radio Station for accuracy. The clock made an electrical contact once each minute to furnish impulses to a stepping relay of the coder, which regulated the functions of the Radiobeacon Station.

A vessel at sea on the same radio frequency received these signals from the various stations transmitting in the area. Using charts, a navigator could more accurately pinpoint the vessel's location by the times and signals were received. Clocks used for this purpose had to be kept synchronized to within a very narrow variance, perhaps a microsecond.

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About This Item

  • Title: Master time control clock, Cape Elizabeth, ca. 1950
  • Creation Date: circa 1950
  • Subject Date: circa 1950
  • Town: Cape Elizabeth
  • County: Cumberland
  • State: ME
  • Media: Metal and wood
  • Dimensions: 160 cm x 51 cm
  • Object Type: Physical Object

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For more information about this item, contact:

Museum at Portland Head
1000 Shore Road, Cape Elizabeth, ME 04107
(207) 799-2661

This Item is protected by copyright and/or related rights. No Permission is required to use the low-resolution watermarked image for educational use, or as allowed by the applicable copyright. For all other uses, permission is required.

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