Graphite-Controlled Mono Synth

Here’s a cool little mono-synth you can make cheaply with a 7555 that uses the graphite from pencils as a variable resistor.

Step 1: Parts List

Parts You’ll Need:
-Solderless breadboard
-22 awg solid core wire
-7555 Timer
-2 1kΩ resistors
-1µF capacitor
-9V battery
-battery clip
-9V to 5V voltage regulator
-graphite pencil and paper
-electrical tape
-audio cable and speakers or headphones

If you're new to electronics or working with breadboards, check these out:
ICs, 555: http://www.instructables.com/id/Know-Your-IC-555-Timers/
Breadboards video: http://www.instructables.com/id/Breadboard-Basics/
Breadboards how-to: http://www.techdose.com/electronics/How-to-Use-Solderless-Breadboards/252/page1.html