Power Supply

[jjucius]

Hi
I need help, i am building an effect like a capitan coconut, it will be a fuzz face a univibe and an octavia in one box, now my question. the univibe uses 15v dc and the other two use 9v dc how can i run all off of one power supply? the univibe has a regulator and the others were ment to run off batterys. i want to use a wall adapter that puts out around 15 to 24 v dc. any help.
Thank you
Joe

[Peter Snowberg]

Welcome Joe,

Luckily the solution is very simple. All you need is a 7809 voltage regulator and a small capacitor (something like 1uF).

Attach the +15 volt supply from the Univibe to the regulator input, attach the regulator ground to your circuit ground, and then attach the regulator output to your 9V negative ground effects. Add the capacitor from the regulator output to ground, and there you go.

The FuzzFace presents its own problems because they're often based around a "positive ground" design. Since you're building the effects, I would heavily suggest using a “negative ground” version of that effect. There are lots of schematics out there to choose from.

This datasheet does not show the 7809 specifically, but the whole 78xx family of fixed regulators is used the same.
http://www.national.com/ds/LM/LM340.pdf

As you raise the DC voltage going into the regulator, it will produce more and more heat so be sure to use a small heatsink if it gets too warm, or just bolt it to the case (probably the best way to go) with a little zinc oxide thermal grease. Keep in mind that the metal tab of the regulator is also a ground connection.

Take care,
-Peter

[jjucius]

Thank you for your fast reply, i was thinking the same thing but i wasent shure. and yes i am making all negative ground. again thank you.
Joe