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ID = 10392
Great Britain (UK)
Brand: Mullard Radio Valve Co. Ltd.;
Developer: Mullard Radio Valve Co. Ltd.;  
Tube type:  Vacuum Pentode   Universal 
  Ca. 1925 up to 1945 rare.
Identical to VR56 = EF36 = 10E/11402 = CV1056 = 1260 = ZA13352 = 5A/157D

Base Octal (Int.Octal, IO) K8A, USA 1935 (Codex=Uf) Top contact with a cap
Was used by Military and/or Government
Filament Vf 6.3 Volts / If 0.2 Ampere / Indirect / Parallel / series AC/DC /
Literature Taschenbuch zum Röhren-Codex 1948/49   
Babani, International Radio Tube Encyclopaedia   Pages 156-157
Electronic Universal Vade-Mecum, Electron Valves and Semiconductor Devices

Patrice Zeissloff

VR56: RTT 1974 (Franzis) 13. Auflage
Martin Renz


Usage in Models 1= 1946? ; 1= 1949

Quantity of Models at with this tube (valve, valves, valvola, valvole, válvula, lampe):2

Forum contributions about this tube
Threads: 1 | Posts: 3
Hits: 1162     Replies: 2
VR56 (VR56)
Júlio Branco
  1 The VR56 is a pre-WW2 military receiving pentode valve. The VR prefix in the type designation stands for Valve Receiving.
The valve in civilian name is an EF36. This valve was obsolete by the 1960s, and our data sheets show that the EF36 had identical characteristics and pin connections to the EF37 and EF37A. These were all high gain low current intermediate frequency amplifiers in superhet receivers and all featured external metalisation. With their low capacitances they would be useful at radio frequencies as well as IF.
It is interesting that as the series progressed, and eventually only the EF37A was produced, the valve had acquired the characteristics of low noise and low michrophany and the EF37A became a standard audio pre-amplifier for professional use before the advent of the EF86.
The wide glass tube envelope is 29 mm in diameter and, excluding the IO base pins, is 81 mm tall.

Best Regards
Júlio Branco
Ernst Erb

Dear Julio

Can you please edit this and select English as language? It is now in "other language" - but your wording is in English.

I did already change texts for you - but then my name apears in your post ...

Just above the title in your WYSIWYG-Editor you see language selection.
There are probably many readers selecting only for English. Those would never see your work.

Júlio Branco

Mr. Erb,

Thank you for having called me to the attention. I had not repaired in this detail.




Júlio Branco


Already one is corrected.


End of forum contributions about this tube

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