AW: Common supply

[Maarten Halmans]

Merlin Zener wrote:

> As I wrote a while ago, I used to make up custom made supplies for
> people who needed this kind of thing. I used hand wound toroids
> with seperate windings for each rail.
>
> Not cheap...

Mine was cheap, I made such a power supply a couple of years ago. I unwounded the
secondary windings of an old transformer. Then I calculated the number of
windings to get 9 Volt. Rewound it with the desired number of windings per
secondary winding. It had 8 secondary windings, so it took me a lot of afford and
time to get in the old transformer. It worked perfectly. After 3 months the
primary winding broke down because I made a calculation error on the primary
current.
So I use wall warts again.