Here is the power conditioner I built.
The enclosure is a Bud CN-6702 from Mouser. Paint is a botched Rustoleum hammered spray. I wanted it to be white, so I bought a can of their ivory hammered paint. It was junk. No hide ability, no hammering. It was like a blotchy transparent metallic white. I painted over it with one coat of the paint I used for my input and output buffers, and decided it was good enough.
This mounts on the underside of my board. There are two superbright white LEDs to show it is powered up, and provide some cool under-board lighting without creating glare.
There are two identical regulator circuits. My goal with that was to spread the load and the heat dissipation. I also thought that if I have two digital pedals that conflict and make power supply noise, I could put them on different regulators and hopefully stop the noise.
As a result, I am sure the filtering is overkill– I used a 1-Watt 3R resistor, two 470uF in parallel, and some ceramic caps on the input of each regulator, and 100uF and some ceramic caps on the outputof each regulator.
You might notice the diode inserted between the regulator pin connected that is supposed to be connected straight to ground, and ground. This is a little trick that lifts the voltage by the Vf of the diode. This way, my power supply puts out about 9.6V, or roughly a brand new 9V battery. This gives me a little bit of headroom, so I can use an R-C filter at the input of each of my pedals, and not worry too much about the voltage falling below 9V.
If you can’t tell, the power in my house is very noisy… heh.
Here are the project files. Included is an ExpressPCB Schematic and PCB file, along with a PDF ready-to-transfer image. Power Conditioner – Schematic, PCB, Toner Transfer [ZIP]
Questions? Comments? Criticism? Compliments?