McVitie Weston valve collection
- Made:
- 1919-1920 in United States
This image is released under a CC BY-NC-SA 4.0
Licence
Buy this image as a print
BuyLicense this image for commercial use at Science and Society Picture Library
LicenseFirst production dull emitter triode, type D.E.R
Science Museum Group
© The Board of Trustees of the Science Museum
First production dull emitter triode, type D.E.R., B4 base, (RMW/C20A - McVitie Weston number), by Marconi Osram Valve Company Limited.
