Please click your language flag. Bitte Sprachflagge klicken.


Information - Help 
ID = 8548
United States of America (USA)
Tube type:  Pentagrid-Converter (Heptode)   Frequency converter   Controlling (mu) 
Identical to 2A7S = PH2A7 = Ut2A7 = CV787 = Ut-2A7 = PH2A7
Similar Tubes
Other shape (e.g. bulb type):
  2A7 ; G-2A7-S

Base 7-Pin-Base U7A = small, old, USA (Codex=Mh) Top contact with a cap.
Was used by Radio/TV-reception etc.
Filament Vf 2.5 Volts / If 0.8 Ampere / Indirect / Specified voltage AC/DC

Which differences of characteristics between 2A7S and 2A7 ?

Babani's International Radio Tube Encylopedia gives a different Ig2 current as a 2A7, but Brans Vademecum 1945 and 1961 gives as electrical equivalent. The shield on this tube is metallised paint. Replacement tubes made by National Union, Raytheon and Sylvania utilised a sheet metal shield. 
Text in other languages (may differ)
Dimensions (WHD)
incl. pins / tip
x 116 x 38 mm / x 4.57 x 1.50 inch
Weight 39 g / 1.38 oz
Tube prices 1 Tube prices (visible for members only)
Information source Taschenbuch zum Röhren-Codex 1948/49   
Babani, International Radio Tube Encyclopaedia   
-- Collector info (Sammler)
2A7S: foto valvola della propria collezione
Antonio Varrica

Emilio Ciardiello

2A7S: Babani 1949-1951
Patrice Zeissloff

from Just Qvigstad

Usage in Models 1= 1933?

Quantity of Models at with this tube (valve, valves, valvola, valvole, válvula, lampe):1

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]