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4P10C or 4Π10C tube, any member familiar with?

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Hi everyone,

the 4P10C is a forgotten Russian octal pentode with plate cup (not MO) that has a 15W dissipation with specs close to EL34 (though it looks like a KT66 having a similar size box plate but smaller plate wings).

I don't see anything in the net about it.

I do have it's detailed specs as can be found on a paper packed by the factory inside the tube box.

Any member that has tested it in a project?
 
Data sheet

Hi, attached you will find the data sheet. If you look at the bottom of the page I have the comparative test results performed on my AVO tester at Va=300V, Vg=230V and in all cases at a bias voltage that gave a plate current of 50mA.

The tubes compared were the following:
5881 S=5mA/V,
KT66 S=6.5ma/V and a
Philips EL34 S=9.5mA/V.

The 4P10C at the above conditions gave an S=8mA/V.
 

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Here are pictures, to compare with 6P3S

...hmmm... I could not attach the pictures:

"Your submission could not be processed because a security token was missing.

If this occurred unexpectedly, please inform the administrator and describe the action you performed before you received this error."

i also get the same message, so what i do is upload pics one at a time....

can you link me to a good seller of these tubes?
 

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4P10C tubes

Since then I built some amps with them. Gorgeous!

Edelweiss-3

Edelweiss-2

Excellent, so in my next amp the finals will be 4P10C. As I have to build a power amp with 6146's ppp (4pcs/ch) the 4P10C's may temporarily sit in one channel. G2's are powered through tertiary windings, Acrosound style. The Mazda octal sockets thanks to PRC are already here!
 
I made one amp using Raytheon VT127/CV1127 made for RAF. The sound and working conditions are like 4П10С, but the tube internally is different. Instead of flat cathode, grids and anode, it uses internals similar to 807, oval-shaped.
What is funny, tubes were never de-classified, so it is impossible to find printed data except test conditions. They were used in radar monitors, were quite linear for better pictures, unlike later sweep tubes that worked in pulse mode.

Matthew Willims - I contacted Anatoliy regarding an amp... | Facebook
 
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