[ARC5] 6V sub for 12A6 - 6C5

[Kenneth G. Gordon]

On 18 Oct 2012 at 11:25, gordon white wrote:

> Yes, probably a 6K6. In one of my receivers the tubes are all 6 volt
> types with a 6C5 in the audio socket, which makes no sense

Actually, yes it does: for both tubes, the plate is pin 3, the grid is pin 5, the 
cathode is pin 8, the filaments are pins 2 and 7, and the internal shield is pin 
1.

Therefore, a 6C5 COULD have been used in place of a 12A6. What you 
would end up with is a triode audio output stage instead of a pentode stage. 
Screen connections would have been ignored and would have no effect on 
either the receiver or the tube.

I would be very interested to learn how the audio output would change with 
that substitution.

Perhaps the original owner only had a 6C5. I think that substitution is very 
clever. Obviously, the original owner did some careful checking before he 
plugged it in.

Ken W7EKB