>
>On Sat, 29 Nov 2003 08:10:10 -0800 R. Measures <r@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...
>
** true
> 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?
** it might. However, tuning up for the specified screen -I will do the
job.
>
> Incidentally, the control grid is swamped with a 50 ohm R so, stability
>is not a concern.
** provided that there is minimal L in the 50-ohm termination.
>
>73 & Good morning,
> Marv WC6W
>
** tnx for coupler, Marv.
>
>
>
>
>
>*
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