Zither switch with open-wire multiple and two-motion ratchet drive, 1894

Made:
1894 in Indiana
maker:
Strowger Automatic Telephone Company

Buy this image as a print 

Buy

License this image for commercial use at Science and Society Picture Library

License

Buy this image as a print 

Buy

License this image for commercial use at Science and Society Picture Library

License

Buy this image as a print 

Buy

License this image for commercial use at Science and Society Picture Library

License

Buy this image as a print 

Buy

License this image for commercial use at Science and Society Picture Library

License

Buy this image as a print 

Buy

License this image for commercial use at Science and Society Picture Library

License

Science Museum Group Collection
© The Board of Trustees of the Science Museum

Science Museum Group Collection
© The Board of Trustees of the Science Museum

Science Museum Group Collection
© The Board of Trustees of the Science Museum

Science Museum Group Collection
© The Board of Trustees of the Science Museum

Science Museum Group Collection
© The Board of Trustees of the Science Museum

Zither switch with open-wire multiple and two-motion ratchet drive, made by the Strowger Automatic Telephone Company, Indiana, United States, 1894.

This automatic selector switch was first used in the LaPorte (Indiana, USA) telephone exchange in autumn 1894. It used piano wire and a contact arm that could move in two directions to select the chosen wire. It was the first switch to use the basic mechanism that would be used in later step-by-step switches at telephone exchanges, and was proposed by the brothers John and Charles Ericsson. Its layout gave rise to the nickname 'zither' switch. The design was only used for a short time before it was replaced by the more familiar step-by-step switch.

Details

Category:
Telecommunications
Object Number:
1970-543
Materials:
metal (unknown) and wood (unidentified)
Measurements:
overall: 550 mm x 450 mm x 240 mm, 22kg
type:
electric switch
taxonomy:
  • component - object
credit:
Donated by Plessey Telecommunications