Another "old" volumen control tip?

[chocopower]

Hi!
have any try this?

http://www.google.com/patents?id=pSI3AAAAEBAJ&printsec=abstract&zoom=4#v=onepage&q&f=false

Mixing fixed and cathode bias for the output tubes is nothing new, but here they are using a reostat in the "cathode bias" section as power control...

Weird?
Dangerous?
Posible?

[PRR]

It's not "dangerous".

I don't think it will give any large reduction of power with the values cited, except maybe that the phase-inverter (not covered or detailed) will overload.

[Tiny_Daddy]

There's plenty of amps out there that have a switch across the cathode resistor. Really that's all you need.

[jojokeo]

  This caught my eye in glancing and immediately gave me a memory out of the past from the movie 2001: A Space Odyssey. "I am a HAL 9000 computer. I just picked up a fault in the AE35 unit. It can only be attributable to human error..."