I was thinking about attempting a variable SMPS. While doing some searching online I came across this circuit and was hoping to get some feedback/opinions on it.
http://www.eleccircuit.com/wp-conte...lator-switching-0-50v-5a-by-tl494-mj15004.jpg

If anyone has a better circuit than this providing a variable output I am open to suggestions.

 

I came up with these awhile back; both could be run off the same 20v-36v unregulated supply. Both are rated for 2.5A; could go to 5A by changing the regulators to LT1170's. Pretty simple. You can add meters if you wish.

In the 2nd schematic, L3 is optional - but helps considerably with the power dissipation in R5. Without it, R5 will dissipate around 1W.

 

Thanks sgtwookie