Archive for 2008
Thursday, May 1st, 2008
Creating a PCB Image using Export
If you want to etch a PCB with a layout in Eagle then you will need to create an image like this one to transfer your design. This brief tutorial explains how to set things up so that you can use the Eagle export command. … more …
Wednesday, April 9th, 2008
Slide Switch Tutorial
When building stomp boxes, slide switches have certain advantages over toggle switches. They are less expensive and more durable than toggle switches, which can easily get broken off by clumsy feet or by mishandling. But they can be trickier to fit, requiring a rectangular cavity to function correctly. Here’s a way to fit a slide switch, using only a couple of simple tools. … more …
Monday, February 25th, 2008
The Noomerang
The Noomerang is a wah pedal by B Tremblay of runoffgroove.com fame. It’s a variant of the Maestro Boomerang wah, which itself is a nice alternative to the usual Cry Baby clones, with some added goodies. … more …
Sunday, February 24th, 2008
The Hornby Skewes Zonk Machine
Yo. Here’s a layout I did for the Hornby Skewes Zonk Machine. I used the schematic from the Fuzz central website. I put an extra pad for the .47 cap since I couldn’t find a package big enough for the Xicon greenie .47. … more …
Friday, January 11th, 2008
Voodoo Lab Overdrive
I have various reasons for putting this one together. My interest was peaked when the Voodoo Lab Overdrive was associated recently with the Fulltone OCD. I was also looking for a relatively simple circuit with op-amps that I could use for an Eagle layout tutorial that I plan to write. In addition, I have been working up my understanding of op-amps through writing a series of tutorials and the divided negative feedback tools are really useful with this circuit.
There are a bunch of mods to consider with this circuit, all of which have been applied to other stompbox circuits over the years. And if the reports are accurate, similar mods appear in the OCD as well. … more …
Tuesday, January 8th, 2008
Op-Amps 4: Divided Negative Feedback
Simple negative feedback, connecting the output to the inverting input, makes an op-amp into a unity gain amplifier. In that setup, all of the output goes to the inverting input. If instead the amount of feedback is reduced, through a voltage divider, then the gain of the op-amp circuit becomes greater than one. This may be the most common way op-amps are used for amplification in stompbox circuits. In addition, by adding some capacitors to the voltage divider, the gain also gets some tonal character that is the foundation of dozens of famous distortion and overdrive pedals (think Boss, Fulltone, Ibanez, Marshall, Proco, Voodoo Labs, …). … more …