power source question

[Roel Das]

Hello everyone,

I'm building a power source for my midi CV. It should have -15V, +15V, +5V,
and seperate dig and analog ground. (They meet at the groundplane under the
DAC.) Which is the easiest way of doing this? It runs from 1 wall wart, 18V
AC. (Is this enough?) (Now it's actually running from 15VAC, but I've seen
alot of articles that say this ain't good...)(And probably it isn't...)

Anyone got a schematic of the perfect power source near? What I had in mind
is just 4 diodes (1N4007),resistors and caps, 7815 and 7915, and more
caps...
The digital part would be the same, but with just 1 diode.

Is there a way to use the regulated +15V as input for the 7805, and still
keeping the grounds seperated? For example, by putting a resistor between
the 2 grounds or something?

Thanks!
Roel

PS: the final version of my text is finally available at my webpage. I won't
be updating the page until July, when I'll translate the text to English,
and put some of my home made stuff on the site... Pictures and everything...