-15v / +15v from 30VDC Adapter '?

[petemoore]

What would you suggest for obtaining a 15+ / 15-vdc supply from a 30VDC adapter [from an old printer]?
 It would be used to operate small signal amps like in my inductorless wah.

[puretube]

http://diystompboxes.com/sboxforum/viewtopic.php?t=23268&highlight=circuit

[Paul Perry (Frostwave)]

Not sure that the reply above was relevant, that is a DC supply.
I think an 'active splitter' circuit would be more like it.
Of course, it all depends what you want to drive with the supply.
WARNING: if it is an unregulated 30v DC, then be careful that whatever you make the active splitter from can handle any overvoltage (a lot of common op amps have max power supply ratings of +-15 or +-18, which gives no safety ratig at all).
I'm thinking of an active splitter made from an op amp with a power transistor pair added on the output (but in the loop) to give sufficient current.
It isn't really as easy at it looks.. but what is? :roll:

[niftydog]

perhaps a commercially available DC DC convertor module?

Switch mode supply?

I like Pauls idea, and there's probably something out there like it.

[puretube]

ooops, I missed the D in the 30V-adapter - sorry folks  :oops: shame

[spongebob]

Is it possible to open the psu adapter? If it's a simple linear PSU (not a switching one) - and the enclosure is big enough - then you could still do what puretube described, there *has* to be AC somewhere in there!  :lol: