[Amps] Life on the Screen?

[Radio WC6W]

On Sat, 29 Nov 2003 08:10:10 -0800 R. Measures <r at somis.org> writes:
> 
> 
> >  The Collins 30L-1 (811A's x4) uses the Plate-Grid capacitance of one
of
> >the tubes along with smaller than typical grid bypass caps plus a
small
> >RFC back the the grid return to implement this same type of divider.  
> >

> >    Could the Plate-Screen capacitance of a Tetrode (4CX250, 4CX1000A,
> >etc.) be employed in a similar fashion if the screen was bypassed with
an
> >appropriate value capacitor.
> >

> **  If the screen is bypassed, there is no signal potential on the
screen 
> - and it can not be used for such.

   Depends upon how well bypassed...

   I have a 4CX1000A/4CX1500B amp which I'm in the process of...
updating.   It has an SK-800 socket which has an integral 1500 pf screen
bypass cap.   

  There is additional screen bypassing mounted right at the socket.  I
was just wondering if removed those caps and added a small choke as in
the 30L-1 then, would the plate-screen/screen-bypass capacitance
"divider" (approx. 100-1 ratio) provide a useful tune&load reference
signal?

  Incidentally, the control grid is swamped with a 50 ohm R so, stability
is not a concern.

73 & Good morning,
   Marv  WC6W







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