Hey guys I need some circuit suggestions...

[adding_to_the_noise]

So for some extra credit in my circuits class my teacher suggested that we come up with a  "hardware homework" that demonstrates some of the ideas we've learned in class. Since we have covered op-amps and active filters and such, I thought that a stompbox circuit would be a cool idea to submit. Do you guys have any suggestions of a circuit that would be good? I would prefer it to be super simple since I have to completely analyze it and write equations and the like. Something with an op-amp and one or two filters would be nice, maybe a booster or and eq or something. So suggest away...

[dschwartz]

what about an opamp wah? or even easier an inductorless wah?

[bkanber]

If you've done transistors in class, you can try analyzing the Fuzz Face. It's a pretty simple two transistor circuit. The transistors are arranged almost like a Darlington pair (which are great to analyze and might get you extra credit).

If your class is advanced, you can try analyzing a phase shifter-- you have to analyze the phase shifts (part of impedance) for that

[adding_to_the_noise]

Phase shifter sounds cool, i'll give it a thought. And sadly, it's a class about linear circuits so no transistors yet...

[theblueark]

Since we have covered op-amps and active filters and such

Sounds like a booster with an EQ just begging to be built.

Equations can show how the opamp boosts the signal by varying the resistance. And how the EQ portion cuts the frequencies at the calculated knee. Do a high pass and a low pass.

This way you don't even need to bring a guitar, just plug an mp3 player into the box.

[oldrocker]

Maybe a Phuncgnosis from circuit snippets.  A cool autowah with filtering and dual opamp.  Or maybe another project at Circuit Snippets website.  They're simple and easy to decipher.
http://www.geocities.com/tpe123/folkurban/fuzz/snippets.html

[oldrocker]

Maybe you could build a White Noise Generator?  It fits all the criteria for the class and Dick Cappel explains where to ad caps to adjust roll off of the filters.  I uses 4 op amps and fits into an Altiods tin.  Look at the bottom of the thread below for the updated schematic I made.  It's much easier to read than Dick C.s
http://www.diystompboxes.com/smfforum/index.php?topic=67164.0

[AceLuby]

Why not a simple DOD 250?  Should fit the criteria and there's a lot of info on it here...