Power Supply

[aparlett]

Hey Guys

Looking for a cheap power supply that has +/- output round $100 mark? nothing too high powered just to play around with precision op-amps.
any suggestions will be a great help.

thanks

[eevblogfan]

hey

Why dont you use cheap ass 12~ 30V 9W or so wall wart and use voltage splitter creating virtual ground using Lm358 one pot and pair of NPN and PNP power transistors ?  I don't have the schematic now 

pleas some one give him the proper schema 

all I can find now is that ( should be good anough as op amp baiasing supply )

http://www.circuitstoday.com/wp-content/uploads/2008/08/voltage-splitter-using-opamp.JPG

Cheers

[IanB]

If you only need a few milliamps than back-to-back 9 V batteries will work fine.

[aparlett]

Im going to uses two 9 volt batteries for now but would like to have a proper supply as im going to be suing it alot more in the future.

[eevblogfan]

hey


Schema is the first photo and the final circuit I've built ( including Lm317 , but not really needed I think ><" )

[aparlett]

thanks that looks pretty good to get me through until i can get a better supply

[aparlett]

any suggestions as off the self ones i can start looking into as well or are they out of price range

[eevblogfan]

I am afraid the "good " one ( e3630A) is out of range unless you can get it locally for that 100~120$ ( which I don't think you can , but give it A chance )

I don't know any other +/- supply to recommend though I am absolutely sure there are few more out there