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ID = 3612
United States of America (USA)
Brand: Common type USA tube/semicond.
Developer: General Electric for Brand RCA-Radiotron; Bridgeport CT, Syracuse NY 
Tube type:  Gas Triode   Detector 
Identical to UX200 = 200_UX = X200 = CX300 = RayX-200 = B-200_UX
Similar Tubes
Normally replaceable-slightly different:
  00 ; 2950 ; 4602_WLS ; DX200 ; EX-200 ; SX200 ; SY200B ; UX200A
First year 1925 70 Years of Radiotubes and V. page 17
Production stop 1926
Predecessor Tubes UV200  
Successor Tubes 1926   UX200A   200A  

Base UX-Base (4 Pins (2 thick, USA 1924, UX)
Was used by Radio/TV-reception etc.
Filament Vf 5 Volts / If 1 Ampere / Direct / Battery =

Tyne page 308ff brings the details of history. Here the main points only:
The first tubes RCA is marketing in 1920 are the detector tube UV200 with argon gas filling and the UV201 Amplifier. Manufacturer was General Electric (GE). Both tubes are operated with a filament current of 1 ampere and at 5 volts. Both have pear-shaped bulbs and are tipped. The base has a mantle of brass with a ceramic insert in thich the pins are imedded. Cunningham is naming his as C-300 and C-301.

In 1925 (Stokes page 17) RCA replaces the UV200 with the UX200.

In May 1926 RCA announces the UX200A as a new detector tube, replacing the UX200. The UX200A contains caesium vapor isntead of argon gas of the UV200 and UX200 to get a much more stable operation and increase of sensitivity. The UX200A has a thoriated filament but at that time, 1926 was already outdated and only used as replacement for UX200 (EE).

Text in other languages (may differ)
Dimensions (WHD)
incl. pins / tip
x 108 x 45 mm / x 4.25 x 1.77 inch
Weight 47 g / 1.66 oz
Tube prices 2 Tube prices (visible for members only)
Information source Saga of the Vacuum Tube, Tyne   p. 316
Tube Lore (II)   p. 25

uxsockel_9.png UX200: KoBi
Konrad Birkner † 12.08.2014

Just Qvigstad
Usage in Models 10= 1925 ; 2= 1928

Quantity of Models at with this tube (valve, valves, valvola, valvole, válvula, lampe):12

Collection of



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