Mystery tube

[100decibels]

A friend ask me if i can repair a vintage DIY PA tube amp he own. I found a bad
diode but there's no identification on the power tubes, externally they are very similar to 6V6GT but the number of pins is different. Someone know?

 

[TonyTecson]

pins 2 and 7 for heaters, 3,4,5 pins are all there, belongs to the 6l6 family of tubes...

 

[MrCurwen]

Probably a 6V6GT.

I'd set up a simple test circuit set up for one of the typical use values in the 6V6 datasheet. See if it sets up like described in the datasheet.

 

[TheGimp]

If the tube is bad and you have to replace it, bust the glass and trace the pins to the appropriate elements. That and a good look at the internal structure will help you identify it.

 

[LAZAROIU]

A friend ask me if i can repair a vintage DIY PA tube amp he own. I found a bad
diode but there's no identification on the power tubes, externally they are very similar to 6V6GT but the number of pins is different. Someone know?

It is 6P6S Russian electronic tube, see pictures below: