> BTW, 60uF is probably more smoothing capacitance than you need, by a
> factor of 2. This is a case where more is not better. The additional
> capacitance is mainly storing up energy and potential trouble if you do
> have a flashover, and will stress the limiting resistor and the
> valve/tube more than strictly necessary.
> (Sorry it's a bit late to mention this, but sometimes we get sucked into
> choosing electrolytics because they're available, rather than because
> they're the right value.)
>
I am in the same boat as Ian; I don't know what you are trying to test.
There is a detailed bulletin by Eimac that has been thoroughly discussed
here on the reflector on how to test a power supply for proper glitch
protection, depending upon what your tube line-up is to be. For most
typical legal-limit ham situations, the B+ is shorted to B- with a #40 awg
wire. The primary breakers/fuses should blow without burning the wire
or blowing up the glitch resistors if all is set up properly.
There is a graph in Bill Orr's handbook that confirms what Ian said about
filter capacitance. I look at this like I do ground radials...above 40 mfd,
or 40 wires,the improvement is very small.
(((73)))
Phil, K5PC
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