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ID = 3609
United States of America (USA)
Developer: General Electric Co. (GE); Bridgeport CT, Syracuse NY 
Tube type:  Triode, vacuum   Universal 
Identical to UV201A = C301A = 201A_Japan = 221D = 201A_Star-Tube = 201A_UV-base = 1A = R221-D = DC201A_UV = C5 = 0201A = U201A = A_UV-base = S-J1 = 2955 = 2970 = J-201A = B201A = CT201A = 2956 = 401A_UV = GS-201A = S-201A_platron = 01A_UV = SW501A = 258_annaka = M201A_UV = Super-6 = C_Radex = P.V.F.301-A = S4000_Schickerling = E_seagull = RT-201A = M201A = OH501A = D-201-A = DX201A_Victor = SV201A
Similar Tubes
Normally replaceable-slightly different:
  201A_Philips ; 2964 ; 5VA_vanHorne ; A201_Volutron ; Amplifier_Harp ; Amplifier_KenRad ; C-201-A ; DV2 ; KR-Q201A
Heater different:
  501A ; C301 ; UV201
Other base:
  PR52_Condor ; R221-DX
First year Dec.1922 Saga of the Vacuum Tube, Tyne page 314
First Source (s)
Dec.1922 : Saga of the Vacuum Tube, Tyne p.314/ New York Radio Show
Predecessor Tubes UV201  
Successor Tubes UX201A   201A   R221-DX   GX201A  

Base UV-Base (4 Pins+Bayonet, USA 1914 WE)
Was used by Radio/TV-reception etc.
Filament Vf 5 Volts / If 0.25 Ampere / Direct / Battery =

Tyne page 314+315: "The UV201A, which was announced at the same time as the UV199 at the New York Radio Show in December 1922, had been desigend to utilize a thoriated filament in the existing UV201 structure and to replace the UV201. The electrode assembly of the UV201 was somewhat larger than that of the UV199, so manufacturing modifications were relatively simple. Work on production procedures was started in Nela Park and Harrrison in April 1922 and progressed rapidly. In October 1922 manufacture of the UV201 was discontinued and production of the UV201A was initiated. ...By August 1923 it was sold more widely than any other tube. ... Late in 1923 the anode and grid structure of the UV201A were changed to increase the mutual conductance of the tube."

Tubes made at the Harrison factory had magnesium as the getter, giving a sharp "mirror" internal appearance. Tube made at Cleveland had a phosphorus getter, giving thr tube a "smoky" internal appearance. All UV201A tubes made at the GE factories had the GE logo stamped on them and a paper label stating RCA in red ink. This label has come off with age in many instances. A photo showing the comparison is now uploaded.

See "Tyne..." for further information about the problems for Neutrodynes. The tipless construction and molded base for the UV201A were introduced in 1924 and soon after this the phosphorus getter was abandoned at Nela Park for a magnesium getter. August 1925 the UV201A was withdrawn from the market for the UX201A.

Nela Park in East Cleveland, Ohio, is now the headquarters of GE Lightning. Wikipedia: "Development of the site was started in 1911, when the National Electric Lamp Association (NELA) was dissolved and absorbed into General Electric. It was the first industrial park in the world, and was added to the National Register of Historic Places in 1975." Harrison was also the sales offices of General Electric Company. When the merger of Thomas Edison "Edison Electric" and Thomson-Huston took place to form GE, one factury had to go, so they made a test on 50 lamps for quality to decide which had to stop making lamps. The Edison lamps from Harrison were declared superior to the Thomson-Houston lamps from Lynn. Harrison kept the lamp works and GE consolidated manufacture of lightweight electrical equipment at Lynn.

Text in other languages (may differ)
Dimensions (WHD)
incl. pins / tip
x 107 x 45 mm / x 4.21 x 1.77 inch
Weight 49 g / 1.73 oz
Tube prices 32 Tube prices (visible for members only)
Information source Saga of the Vacuum Tube, Tyne   p.298, 313 - 315, 429
Tube Lore (II)   p. 25

uvsockel_5.png UV201A: KoBi
Konrad Birkner † 12.08.2014

Just Qvigstad
UV201A: KoBi
Konrad Birkner † 12.08.2014

Usage in Models 2= 1922?? ; 3= 1922? ; 30= 1922 ; 2= 1923?? ; 17= 1923? ; 122= 1923 ; 5= 1924?? ; 38= 1924? ; 211= 1924 ; 33= 1925? ; 208= 1925 ; 7= 1926? ; 20= 1926 ; 1= 1927? ; 1= 1928 ; 3= 9999

Quantity of Models at with this tube (valve, valves, valvola, valvole, válvula, lampe):703

Collection of



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