Original wheel or steel-disc coherer, 1902

Made:
1902 in England

Creative Commons LicenseThis image is released under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 Licence

Buy this image as a print 

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

Creative Commons LicenseThis image is released under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 Licence

Buy this image as a print 

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

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

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

Original wheel or steel-disc coherer (thin-film detector), made by E E Robinson, England, 1902. Made for Oliver Lodge and Alexander Muirhead

Original wheel or steel-disc coherer (thin-film detector), made by E E Robinson, England, 1902.

By the time that the wheel, or thin-film detector, was developed in 1902, the term 'coherer' was being applied to all types of detector, whether or not they utlised materials which 'cohered' in the presence of Hertzian waves. Edward Robinson, Oliver Lodge's assistant, was principally responsible for devising this detector. The steel disc, with a sharp edge, rotates continuously and dips into a small pool of mercury covered with a thin film of oil. When Hertzian waves are detected the disc makes contact with the mercury and as the disc rotates a fresh surface is continuously being presented to the mercury. It is therefore described as being self-cohering - that is, not requiring a series of mechanical jolts to reset it. This is one of Robinson's bench-top prototypes.

On display

Science Museum: Information Age Gallery: Cable

If you are visiting to see this object, please contact us in advance to make sure that it will be on display.

Details

Category:
Radio Communication
Object Number:
1942-38
Materials:
bakelite, brass (copper, zinc alloy), wood (unidentified)
type:
coherer
taxonomy:
  • component - object
  • radio receiver
credit:
Donated by E. E. and T. H. Robinson
status:
Permanent collection

Cite this page

Rights

We encourage the use and reuse of our collection data.


Data in the title, made, maker and details fields are released under Creative Commons Zero


Descriptions and all other text content are licensed under a Creative Commons Attribution 4.0 licence

Using our data

Download

Download catalogue entry as json

Download manifest IIIF

Our records are constantly being enhanced and improved, but please note that we cannot guarantee the accuracy of any information shown on this website.