Junkyard Jam Band

B   Extra Circuits

This appendix provides a handful of schematics for circuits that might come in handy as you continue to tinker and explore, including generic versions of all of the oscillators we’ve built in this book, a basic amplifier, a stripped-down preamp, and some useful filters and effects. Enjoy!

Super-Basic Continuity Tester

Have a switch you aren’t sure is working right? Or a multi-pole switch whose terminals you need to sort out and label? What about a pile of instrument cables that look fine but might have gotten slammed in a car door too many times? A continuity tester, which tells you whether two points in a circuit are electrically connected, is your best friend in these situations.

Most digital multimeters have a built-in continuity ...