> There are ways to design around this problem, but the only reliable
> way is to use a higher-rated device and/or a lower rail voltage.
.......or to clamp the shunt side of the series resistor with a large
zener with a capacitor across. You can use a zener clamp rated
below the maximum voltage breakdown of the shunt device, and
above the highest desired regulated voltage.
This actually is a good idea in ANY case, because the shunt diode
with protect the screen system if the main regulator goes on
vacation.
73, Tom W8JI
W8JI@contesting.com
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