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History of the manufacturer  

Longlife, the Hague

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Name: Longlife, the Hague    (NL)  
Abbreviation: longlife
Products: Tube manufacturer
Summary:

Longlife, the Hague

Longlife radio tubes 1934 - 1938 5/1934 – 6/1936 Red Star Radio, van Galenstraat 5, The Hague 6/1936 – 2/1938 NV Raho, Wassenaar.

Founded: 1934
Closed: 1938
Production: 1934 - 1938
History:

A.J. Hofmann founded Red Star Radio on 1-10-1933. Red Star Radio was a dealer in radios and radio parts. They advertised Longlife tubes for the first time on 6-7-1934 in Radio Express. From June 1926 the Longlife tubes were sold by NV Raho, another company of A.J. Hofmann. Early in 1938 the Longlife tubes disappeared from the market. They were marketed very cleverly as having a long life (Longlife) because of the bifilar spiralizing of the filament. A bifilar filament is spiralized and bent 360 degrees so that each turn of the spiral lies next to another turn with a flow of electrons in the other direction. The magnetic fields of both turns will eliminate each other, resulting in less hum. This only was done of course with indirect heated tubes.

Red Star Radio did not manufacturer the Longlife tubes. There are reasons to believe that the Longlife tubes were made by Thermion, but there is no proof of that. These reasons are: - Thermion and Longlife got a Philips licence at about the same time in 1934. - When Thermion made an improvement in a tube, a name was added. There are Thermion, Thermion Ultima, Thermion Ultima 1936 and Thermion Selecta tubes. As for Longlife, there were Longlife, Longlife Perfect and Longlife Superior tubes. - The Longlife tubes disappeared from the market in early 1938, when the Thermion Radio Tube factory became bankrupt.

This manufacturer was suggested by Peter den Boer.


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