Please click your language flag. Bitte Sprachflagge klicken.


Information - Help 
ID = 28727
Great Britain (UK)
Brand: BTH (B.T.H.), British Thomson-Houston Co, Ltd.
Tube type:  Triode, vacuum   Universal 
  <1925 very rare. ***
Identical to R4B_BTH = R4B_MO = R4B_Marconi
First year 1922 Saga of the Vacuum Tube, Tyne page 220
Predecessor Tubes R4A  

Base Europe 4-Pin B4 (Eu A, E, 4A) 1914
Was used by Military and/or Government
Filament Vf 3.5 Volts / If 0.46 Ampere

The R4B tube was first made in 1918 and had an E12 base. In the following years, this was changed to B4 but date of the changeover is uncertain.

Text in other languages (may differ)
Information source British Radio Valves - The Vintage Years, Thrower   pages 27 & 40
Saga of the Vacuum Tube, Tyne   Page220

b4_1~~69.png R4B_BTH: Fin Stewart
Fin Stewart

Just Qvigstad

You reach this tube or valve page from a search after clicking the "tubes" tab or by clicking a tube on a radio model page. You will find thousands of tubes or valves with interesting links. You even can look up radio models with a certain tube line up. [rmxtube-en]