Hey guys, i built a real (cheep) quick adjustable power supply using an LM317...
i basically followed the schematic at:

http://expert.cc.purdue.edu/~bymaster/power_supply.gif

anyway, when i check the output voltage on the 317, no matter what values of res
istance i put the adjust pin and the output pin always read 16.8v.  There is a 1
8v input.  The 5v 7805 regulator works fine...  Now i know i probly blew out the
 chip because while testing i turned the 5k pot to 0, there should be 20ohm in s
eries wit the 390ohm resistor and when u do the math

 1.25(1+ 20/390) = 1.31v

In my circuit..the two 10ohm resistors started to smoke and turned black.  Why??
  They are 1/4 wat resistors (probably why but all i had on hand)..???

mikE

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