Grace's Guide is the leading source of historical information on industry and manufacturing in Britain. This web publication contains 167,645 pages of information and 247,064 images on early companies, their products and the people who designed and built them.
Grace's Guide is the leading source of historical information on industry and manufacturing in Britain. This web publication contains 147,919 pages of information and 233,587 images on early companies, their products and the people who designed and built them.
of Farringdon Road, London, maker of valves and cathode ray tubes
Previously Freedman Valve Co
1930-33 Paul Freedman was MD of Freedman Valve Co
1935 Patent to the company and Donovan William Sayers for a portable wireless receiver
Name changed to Hivac.
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MW1.43