Power supply transformer question

[zyxwyvu]

I'm planning on making a power supply based on the spyder at geofex: http://www.geofex.com/Article_Folders/Spyder/spyder.htm.
The article suggests using this tranformer: http://www.smallbearelec.com/Detail.bok?no=597, which seems like it would work very well.

The thing is, I also need an 18V output for some of my pedals. Is it possible to connect two of the secodaries to get 22V instead of 11V out, so I can regulate that down to 18V? If so, how would I wire it? If not, how else could i get 18V?

One more thing: The transformer also has a 9VAC output. Will that work with my Whammy IV? It is supposed to take 9VAC; just wondering if there are any other things that could cause problems.

[brett]

Hi
If all of those 11V windings have a common ground, they are wired in parallel and you can't easily change that to connect them in series to get 22V.  However, you can combine two *independant* 9V DC supplies to get 18V.  In your case the simplest thing to do would be to connect the -ve of a 9V battery to one of the +ves of the supply.  The +ve of the battery is then +18V DC wrt the supply ground.

Altternatively, you might want to use a transformer with separate 9V and 15/18V taps.
cheers

[zyxwyvu]

Thanks for the reply, brett.

After looking at the geofex page again, I noticed under one of the pictures it says the secondaries can be stacked to get 18V. It seems like that is what I had in mind.