[sdiy] Bipolar PS with untapped xformer

[Nathanael King]

> its really no different than the many AC (wallwart) TO DC projects out there...correct ?
Pretty much. This schematic is actually slightly more confusing in my
opinion, but the advantage is it uses two of the same positive
regulators. You can find similar designs by searching for bi-polar
supplies using only positive regulators.
My design of choice for single tapped transformers is essentially the
MFOS wall-wart one. I'm by no means the authority, but I don't think
all the 3300mF capacitors are necessary. I've used between
4700mF-2200mF, then something in the 47-22mF range, then a .1mF. I'm
posting because I feel like being corrected if this is a bad idea.
Never been a problem for me though. I would also add a .1mF on the
output for some additional filtering. Again, just me.
The beauty of doing it that way is it is simple to adapt for dual
tapped transformers (same thing just two more diodes), and negative
regulators are easy to identify and troubleshoot. It can be more
difficult to figure out if you made a *gasp* mistake if using two
positive regulators.

-- 
Nate King
Paper Products Music