>
>All the proponents of grounded grid are violating Rich's Rules - that the
>voltage on the screen grid of a pentode must have constant voltage to
>produce an acceptable signal.
The grounded grid circuit is not grid driven. The rule applies to grid
driven, Class AB1amplifiers.
>
> Yet, in a grounded grid amplifier, the screen grid voltage varies with
>drive - just as the control grid voltage varies. It is not zero volts
>simply because the screen voltage is grounded. Heavy grid and screen
>current flow - contrary to Rich's Rules.
>
>And, in grounded grid, the tetrode or pentode tube is being used in a manner
>other than how the factory intended.
>
>Lastly, many commercial sweep tube amplifiers put out a -22 db distortion
>figure on a good day, if operated according to the factory.
>
Not the ones I have heard. The supercathode drive circuit has low power
gain but it is extraordinarily linear.
- Rich..., 805.386.3734, www.vcnet.com/measures.
end
--
FAQ on WWW: http://www.contesting.com/FAQ/amps
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
|