Hi again..
My current power supply project has been built with a tuned filter on the
negative rail of the DC, tuned to 100hz (i.e. 2xmains hz)
I have a Dahl TX that can give 1.5a, with a 40uf cap. The filter is made up
from a 1.2uf cap with a 2h choke.
All the info I can find on this type of filter indicates that I need to run
a bleed resistor to keep the filter drawing a small amount of current stop
the KV from rising... I've tried a few different sizes of resistors, and to
be honest, I'm not happy with the results. Even with a 110k resistor across
the cap, the running voltage drops from 3.9 down to 2.6(ish)
All this is making me ask myself if it's worth running such a filter at
all... ????
Does anyone else use one, and, if so, was building the supply that way worth
it in the end??
Thanks for any info..
Andy
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