[sdiy] best ways of portable +/- supply

[KA4HJH]

>does anyone have opinions on the best way to get plus and minus rails into
>a portable synth/noisenaker/stompbox type project  WITHOUT using an on
>board transformer?
>
>
>the options I know of are
>
>1.AC to DC conversion (ac wallwart plugs in and is converted with
>regulators and caps to a DC dual supply.  Kind of bulky due to use of
>large caps.

Here is a little known way to get a FWR bipolar supply from a *single* AC
source:

<http://s1115.photobucket.com/albums/k541/MacDoktor/SDIY/?action=view&current=FWR-single-AC-supply.jpg>

I posted this once before about ten years ago. I've used it myself and it
does work.

-- 

Terry Bowman, KA4HJH
"The Mac Doctor"