Please click your language flag. Bitte Sprachflagge klicken.


Information - Help 
ID = 28555
Great Britain (UK)
Brand: Ediswan, Siemens Edison Swan Electric Co.; London
Developer: Ediswan, Siemens Edison Swan Electric Co.; London 
Tube type:  Triode, vacuum   Universal 
  <1925 very rare. ***
Identical to ES4
Similar Tubes
Normally replaceable-slightly different:
First year 1921 Saga of the Vacuum Tube, Tyne page 372, 373, 395
First Source (s)
1920 : History of the British Radio Valve to 1940 p. 155

Base Europe 4-Pin B4 (Eu A, E, 4A) 1914
Was used by Radio/TV-reception etc.
Filament Vf 4 Volts / If 0.75 Ampere / Direct / Battery =

First made in 1920, this tube was designed by John Scott-Taggart and was similar in appearance and characteristics to the R tube. While working for a year from 1919 to 1920, as head of the tube department of Edison-Swan, He designed the ES2 and ES4 tubes. He left to further his radio interests elsewhere. Over the next few years he designed other tubes and some of these were made for him by Mullard. He was a well known author during (and after) World War One and he was in various signals units of the British Army. He was also a technical officer involved in radar training and maintenance in World War Two.

With 1 amp at 6 v to the filament and up to 1000 v at the plate it could be used as a transmitter up to about 30 watts!

Text in other languages (may differ)
Information source Saga of the Vacuum Tube, Tyne   Pages 372, 373 & 395
British Radio Valves - The Vintage Years: 1904-1925   Page 31

b4_base_pins~~214.png ES4: Fin Stewart
Fin Stewart

Just Qvigstad

Collection of



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]