You will need the following items to make the rotating microphone work using my methods:
1 Electret Condenser Element (for this application a unidirectional capsule will work best)
1 Male XLR Connector
1 Female XLR Connector
1 Male 1/4" TRS --> Male XLR adaptor
1 Female 1/4" TRS plug
1 DC Motor (9V) with gear
1 Circular lightweight piece of wood (I got mine at Hobby Lobby)
1 Rubber Gear Strips (long enough to cover the circumference of the wooden circle; matched to motor gear)
1 Glue (Gorilla Glue or something like it)
1 Wood Glue (used for the rubber gear strips and the wooden circle)
1 H Bridge
1 10k resistor
1 2k resistor
1 1000pF capacitor
2 10uF capacitor
1 Analog or digital switch
1 Potentiometer (50k-100k will work)
1 Arduino microcontroller (I am using the Diecimila) including a computer or other way to program the board. You do not need a computer to use the rotating microphone once the Diecimila is programmed and has 9V of power coming in (center positive).
1 9V power adaptor (center positive, not exceeding 300mA)
1 9V battery or 4 AA batteries in a 4 AA Battery Cell Holder
1 breadboard for motor circuit
1 perf board for the mic powering circuit
A good bit of wire and alligator clips
small plastic clamps
Soldering iron with solder
small lightweight plastic bottle with screw on cap (I used a small bottle of Dr. Bronner's Magic Soap)
large plastic bottle cap (to hold the motor in place)
small mic clip
rubber mount for electret capsule (I used one that I stripped out of an Apple PlainTalk microphone)
Step 1: Make the microphone powering circuit
You can also power the microphone using four AA batteries in a four AA battery cell holder.
I chose to make mine with XLR in/out as XLR is usually the type of mic inputs that I'm using.
I went ahead and made the circuit on a perf board- it's much easier to do on a perf board that has some connecting strips for ground, etc.
The microphone circuit that is also shown on the web page will be used later on so bookmark the page for future reference.