[Amps] Super Cathode Driven 4CX250B

[Mike Waters]

Hi Bill,

On Fri, Jul 10, 2015 at 2:03 PM, Fuqua, Bill L <wlfuqu00 at uky.edu> wrote:

>   Well, I am thinking about old projects I have not gotten back to. ...
> the second
> is to make a super cathode driven 4CX250B amplifier. I have considered
> giving it a slight bit of control grid signal, not much, in such a way that
> it is easily controlled to make some measurements.
>

Thanks for sharing this. I just learned something. I wasn't aware that the
super-cathode drive might be a good idea on a tetrode. From reading Tom's
stuff in the past, I got the impression that Bill Orr's design was a bad
idea for ANY tube.
www.w8ji.com/vhf_stability.htm

I have some 4CX250Bs here. Maybe I'll build one of those myself someday for
144 or 432.



>   All, I have left of my 6AG7 amplifier is my homebrew heat sink.
>

You put a heat sink on the tube? I started to use a 6AG7 in an amp circuit
over 40 yrs ago, but never did.

73, Mike
www.w0btu.com