Anyone know about these Voskhod SILVER ANODE 1960-70s Soviet 12ax7's

[Paul Fischer]

Hey Guys,
Looking for some 12ax7's and ran across these Soviet ones. They are much less expensive so I wonder what the deal is. Any experience with these would be appreciated.
Thanks,
Paul

 

[TriodeLuvr]

Those are NOT 12AX7. The 6N2P is more rightly referred to as a 6AX7. It has a non-center tapped 6.3V filament. The filament pinout is different than a 12AX7, so it's not a plug-in replacement.

Jack

 

[Paul Fischer]

Ah. Thank you. That's right...pin 9 looks like it goes nowhere. Geez.

 

[TriodeLuvr]

I've been designing with these for some time rather than the more expensive (but no better IMO) 12AX7. Pin 9 is an inter-section shield that needs to be grounded.

Jack

 

[Paul Fischer]

Inter-section shield? That's a new one for me. What does it do?

 

[TriodeLuvr]

The shield minimizes crosstalk between the two triodes. It's the same type of shield as used in the 6CG7.

Jack