On Feb 19, 12:51*am, "Phil Allison" wrote:




With a full-wave bridge rectifier, if you use an 8300 uF capacitor, the
volts of ripple will equal the amps of load current. *(Don Lancaster
taught me this.)

** The correct value is 6300uF.

Such a cap will drop 1 volt in 6.3mS, the typical discharge time in a full
wave rectifier at 60Hz.

For 50Hz full wave supplies, the value is 7500uF for 1V ripple at 1 amp.

.... *Phil

This is some great advice. Thank you everyone for all your input. I
especially like the diode and Zener ideas. They/re cheap and should
work well. I've got lots of diodes around here and I'm going to
experiment with them. However after all this I remembered that the
transformer is center tapped! At the time, I simply wire nutted the
tap, tucked it down under the transformer and forgot about it. How
this simple fact and the possibilities it presents slipped my mind is
anyone's guess. I've been building this thing in the evenings after my
usual work and perhaps I've been tired. The transformer measures 25.2V
at 120V line unloaded. Loading the transformer in this fashion will
probably unbalance it somewhat and drop the 24V a bit as well but I
don't see it as a real problem. I should be able to use one side of
the secondary and the tap now get at least 15 -17 VDC out of the
bridge and filter, and that will provide a healthier input to my
regulator. Lenny