"Barry Kirkwood" <bjk@ihug.co.nz> said --
>Let us get the arithmetic right:
>Assuming we are talking, say, 3kV @ 1A peak power for the anode, then the
>screen load is trivial by comparison.
>If building from iron collected from surplus sources, then making a 400V or
>whatever supply and tapping off for the screen, and then seriesing this with
>2.6kV to make up 3kV is no big deal.
Or how about using more than one bleeder resistor on the plate supply?
Ferinstance, if you're using a capacitor bank, pick your 450V source off
the next to the bottom capacitor, and you're choppin' in tall cotton.
This assumes a bank with approx. 250 volts across each capacitor.
It gives you a stiff screen supply, not well regulated and totally exposed
to glitches, but it goes away if the anode supply goes away.
Your safe screen supply regulator and protection circuitry would be
downstream from this, obviously.
Tom, I've never seen how you do it because your schematics aren't on your
website. I'm releasing this idea to the public domain because it's SO
obvious that even even a CBer could figure it out. If you decide to
implement it, you owe me. If you've already implemented it -- good work.
Jim N6OTQ
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