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ok, here is a simple thing...i hope so
i have a somputer power suply wich outputs 12V.
and what i want to do is to make a variavle suply....1.2 to 12V possibly uing the LM317
but it needs at least a 3V drop on it so......
also i want to generate +/-12V from the 12V, with the max current of 1-1.5A will be great, and problably use a LM337 for the negative side for making variable -1.2-12V suply.
anybody has any ideas?


Take the 12v supply, feed to a LM257x boost regulator with a twin wound transformer........rectify the 2 secondary voltages and there's your _ & + 12v via your LM317's.........
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