>Rich Measures wrote:
>>>Hi
>>>
>>>I recall a recent very good article about tetrode screen supplys
>>>in QST or QEX. Cant recall which one or the issue.
>>>
>>>Anyone have that info handy
>>>
>>For small tetrodes with less than roughly 800v screens, a zener-string
>>shunt regulator works best.
>
>GW4FRX's measurements quoted in my article (October QEX) show that a
>zener string emphatically does NOT "work best" from the viewpoint of
>IMD!
Volts are volts. It matters not what type of regulator they come from,
unless the regulator is performing poorly.
>
>> For larger tetrodes, a 723-based positive
>>floating series pass regulator has advantages. You can find both types at:
>>http://www.vcnet.com/measures
>
>But note also that a series regulator cannot handle reverse screen
>current, which many tetrodes can generate. You MUST use a shunt resistor
>from screen to cathode, that permanently passes the maximum negative
>screen current that the tetrode can generate. ...snip...
True indeed, Mr. White. But note that essentially the same information
can be found in *Amplifiers* at the above URL.
Rich---
R. L. Measures, 805-386-3734, AG6K
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