Hello. I have an 250va 25v+25v toroidal transformer that I want to add secondary windings to. The secondary windings are to eliminate the need for an additional 12v center tap 3A transformer. I understand the voltage will be determined by number of turns, but what changes the amperage available? Is it wire guage? Also, since I need the center tap, do I make two windings in opposite direction, connecting the start of the windings for the center tap and the ends for the voltage (about 6v+6v for my application)?
Thanks for the help.
Jerry