There is a point of diminishing return for filter capacitance. The Orr
chart is real simple to use.
For serious use, transformers must be specially designed for voltage doubler
circuits. This means very low resistance. Otherwise, you will get a
significant voltage sag when you "ooh" and "aah", which cannot be offset by
extra filter capacitance.
Full wave rectification has less ripple than half wave rectification and I
have seen no circuits for amplifiers using half wave rectification.
Unless you have a hypersil transformer, weighing the transformer will give
you a good idea of the capacity. Heavier is better. A good power supply
will give you a hernia.
On the other hand, Heath had a nice power supply in the SB-220 which was not
too heavy. It made up for weight by good design. When you use junk box
parts, though, heavy is better. When I leave my house for a vacation, I
have never worried about someone breaking in and stealing my amplifier power
supply. I have worried about whether or not I should reinforce the columns
for the second floor, though.
73, Colin K7FM
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