From: "Gerry" 
Subject: RE: [drakelist] AC-4 Cap values

style=3D'font-size:12.0pt'>supply.  When you have a =
"thump" from
turning on a power supply, it 





generally is indicative of too great of a =
surge
current going into the filter 





capacitors and stressing them
unnecessarily.   It doesn't help the =
rectifiers,





either.  Also, I'm not sure that it is a
"leaky" capacitor that causes
the





"thump" you heard at power supply
turn-on....I've always been led to 





believe that the "thump" was from =
the large
flow of current into an





uncharged capacitor, although I've never had =
it proven
to me that this





was the actual
cause.





You could, however, benefit the power supply =
considerably,
by inserting a





resistor of the proper resistance and =
wattage, into
the 650 volt output, 





between D2 and the connection to R1.  =
This would
also serve to bring your 





650 volt HV (now approx. 700 volts, as you =
indicated)
back down nearer to 





the correct 650 volt
value.





Your could also do the similar action with a =
resistor
added between D5 and





the connection to C3, and also reduce the 290 =
volts
down to the original





design value of 250 =
volts.   





Possibly, the original design of this =
power was
slighted somewhat, by not 





including a choke in each of the two =

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