The Musical Maker Mannequin

Just in time for the end of the year parties, comes the Musical Maker Mannequin! The Musical Maker Mannequin is a styrofoam mannequin head with blue LEDs for eyes and a circuit that makes the LEDs blink to the beat of music. When the mannequin is wearing safety goggles, the light from eyes reflects in interesting and cool ways. The circuit for the Musical Maker Mannequin uses just a few inexpensive parts (see diagram), is easy to construct, and makes the perfect decoration for dance parties.

Check out the Musical Maker Mannequin in the videos. Note that digital video cameras are sensitive to light from LEDs and tend to change the color to white, whereas, in real life with human eyes, the mannequin's eyes will be bright blue.

I made this at TechShop.

The Musical Maker Mannequin consists of the following parts:

• Styrofoam mannequin head (photo 1) - I used a child's head because it looked more sci-fi than an adult mannequin head.
• 2 10mm jumbo diffused blue LEDs (photo 2) - Jameco part # 2152147
• 1 TIP31 or TIP31C transistor (photo 2) - Radio Shack 276-2016 or Jameco 179354
• 1 DC Coaxial Power Jack Size M - Radio Shack 274-1577 (photo 3, left)
• 1 DC Coaxial Power Plug Size M - Radio Shack 274-1569 (photo 3, right)
• 1 1/8" Mono in-line phone jack - Radio Shack 274-333 (photo 4, left)
• 1 1/8" Stereo jack to 1/8" mono plug adapter - Radio Shack 274-368 (photo 4, right)
• 1 1/8" Stereo cable with make plugs on both ends - Radio Shack 42-962 (not pictured)
• 1 9 Volt DC power supply (photo 5)
• 2 feet of 1/8" diameter heat shrink tubing (not pictured)
• 4 feet of 22 gauge black stranded hook up wire (not pictured)
• 4 feet of 22 gauge red stranded hook up wire (not pictured)

Optional Parts

• 1 Velleman MK190 5 Watt Stereo Amplifier Kit (photo 7)
• 1 1/8" Stereo cable with make plugs on both ends in addition to the one listed above - Radio Shack 42-961 (not pictured)
• 1/8" Stereo inline audio jack - Radio Shack 274-274 (not pictured)
• 1 4" 1/8" Stereo Y-Adapter - Radio Shack 42-2570 (photo 8)
• 1 foot of 22 gauge blue stranded hook up wire (not pictured)
• 1 foot of 22 gauge green stranded hook up wire (not pictured)
• Power supply for the amplifier. I used a 9.5 VDC 1300mA power supply (photo 9)

Tools Required:

• 23/64" (9.13mm) Drill bit (photo 6, left)
• 3/16" Long drill bit (photo 6, right)
• Electric drill
• Soldering iron and solder
• Wire cutters and wire strippers
• Heat gun or other heat source for shrinking the heat shrink tubing
• Scissors
• Voltmeter (option but suggested)

In this step, the power supply will be prepared as shown in the diagram.

1. Take the 9 volt power supply (photo 1) and cut off the power plug (photo 2).
2. Strip the ends of the wires as shown in the photo 3. Usually the wire with the stripe is the positive wire but I recommend using a volt meter to check the polarity of the wires. If the polarity is incorrect the circuit will not work and the transistor and LEDs may be damaged.
3. Slide the plastic cover for the power plug onto and down the wires before soldering.
4. Solder the positive wire to the short lead on plug and solder the negative (ground) wire to the long lead on the plug (photo 4).
5. Slide the plug's plastic cover up to the plug and screw it on (photo 5).

In this step, the LEDs wiring will be prepared as shown in the diagram.

1. Cut two 24" lengths of red wire and cut two 24" lengths of black wire. Strip the ends of both ends of each of the wires (photo 1).
2. Attach the black wire to the shorter wire (cathode) on the LED (photo 2).
3. Solder the connection (photo 3).
4. Attach the red wire to the longer wire (anode) on the LED (photo 4).
5. Solder the connection (photo 5).
6. Repeat the last four steps for the second set of wires and LED.
7. Cut four 1.5" lengths of heat shrink tubing (photo 6).
8. Slide a piece of heat shrink tubing onto the wire and position them (photo 7).
9. Using a heat gun or a lit match, shrink the tubing (photo 8).
10. Repeat the last two steps for the second set of wires and LED.

Mount the wires into the mannequin head as follows:

1. Carefully thread the LED wires through the holes in the mannequin head (photo 1 and 2).
2. Gently pull the wires so that the LEDs are completely inside the eye holes (photo 3).

Next wire the LED wires in series as shown in the diagram:

1. Twist the ends of one of the red and one of the black wires (photo 4).
2. Solder the two wires together (photo 5).
3. Cut a piece of heat shrink tubing long enough to cover the exposed connection and hold the wires together and then shrink the tubing (photo 6).

In order to keep the wires neat and keep them from tangling:

1. Cut a similar length of heat shrink tubing and slide it up the other two wires and shrink it in place (photo 7).
2. Cut small 1/8" to 1/4" length of heat shrink tubing and slide them onto the wires and place them ever 4-5" and shrink them in place (photos 8, 9, and 10).

In this step the TIP31 transistor will be wired as shown in the diagram.

1. To make it easier to attach and solder the wires to the transistor, gently bend the leads on the transistor (photo 1).
2. Cut a 1/2" piece of heat shrink tubing and slide it onto the black wire from the LED (photo 2).
3. Attach the black wire to the center lead on the transistor (photo 3).
4. Solder the center wire (photo 4).
5. Cut a 12" length of red wire, strip both ends and attach one end to the left transistor lead (photo 5).
6. Solder the left wire (photo 6).
7. Cut a 3" length of black wire and strip both ends (photo 7).
8. Attach and solder one end of the wire to the right lead of transistor (photo 8).
9. Cut two pieces of heat shrink tubing long enough to cover the exposed wires and slide them up over the red and short black wire. Slide the heat shrink tubing from LED wire up as well and shrink them (photo 9).
10. Cut a 12" length of black wire, strip both ends, and attach one end to the short black wire on the right transistor lead (photo 10). This wire will go to the phone jack in step 7.
11. Cut a 6" length of black wire, strip both ends, and attach one end to the black wire from the step above.
12. Solder the wires together (photo 11).
13. Cut a piece of heat shrink tubing and slide it over the exposed connection and shrink it (photo 12).

In this step the the audio phone jack will be connected to transistor as shown in the diagram.

1. Unscrew the plastic cover for the phone jack and slide it up over both the red wire connected to the transistor and the 12" black wire connected to the transistor. Cut a 1" piece of heat shrink tubing and slide it over both wires (photo 1).
2. Attach and solder the red wire to the small terminal on the jack and the black wire to the large terminal on the jack (photo 2).
3. Gently bend the metal tabs on the long terminal to enclose the wires and push the heat shrink tubing up to the terminal (photo 3).
4. Shrink the tubing (photo 4).
5. Slide the cover up and screw it onto the jack (photo 5).

In this step the the power jack will be connected to the TIP31 transistor as shown in the first diagram.

1. Cut a 1/2" length of heat shrink tubing.
2. Unscrew the plastic cover for the power jack and slide it and the heat shrink tubing over the black wire attached to the right lead on the transistor and the red wire from the LED (photo 1).
3. Attach the red wire to the short center terminal of the power jack and attach the black wire to the long terminal. Solder the wires (photo 2).
4. Bend the metal tabs on the jack to hold the wires in place and move the heat shrink tubing up to the end of the jack and shrink it (photo 3).
5. Screw the plastic cover onto the jack (photos 4 and 5).

The wiring is now completed and should match the wiring diagram and look like photos 1 and 2.

It's time to test the circuit:

1. Plug the 1/8" stereo to 1/8" mono adapter into the 1/8" mono jack as shown in the left on the diagram.
2. Plug one end of the stereo cable into the adapter and the other end into your audio source (MP3 player, stereo, etc.) as also shown on the left of the diagram.
3. Plug the DC coaxial power plug into the power jack as shown in the right side of the diagram.
4. Plug the power supply into a wall outlet.
5. Turn on your audio source and play some music with a nice strong beat like the music in the videos on the first page of this instructable.
6. If you don't see the light flash, try turning up the volume. If you still don't see the lights flash, the first thing to check is the wiring. If the wiring looks OK, then the problem is probably that the device you're using to play the music doesn't put out enough power to drive the circuit. I found that my home stereo would drive the circuit but my iPod would not. You may need to add an amplifier to drive the circuit - see the next step.

My iPods did not have sufficient power to drive the circuit so I bought a Velleman MK190 5 watt stereo amplifier kit (photo 1) to increase the output. The MK190 is an inexpensive, very easy to construct amplifier that was exactly what was need to make everything work perfectly. You could any similar 5 watt stereo amplifier to do this.

1. Take the power supply for the amplifier (photo 2), cut the plug off, and using a voltmeter identify which wire is the positive and which is the ground. Often the positive has markings but it's best to use a voltmeter to be sure. I put a small piece of red heat shrink tubing on the positive wire as a reminder.
2. Attach the power wires to the power connector on the amplifier (photo 3).
3. Cut three 6" lengths of wire, one green, one blue, and one black and strip the ends of each of the wires.
4. Attach and solder the green and blue wires to a 1/8" stereo inline audio jack (photos 4).
5. Attach and solder the black wire to the large ground tab on the audio jack (photo 5).
6. Bend the metal tabs around the wires to hold them in place, then slide the phone jack's cover over the wires and screw it on the audio jack (photos 6 and 7).
7. Cut a 1/2" length of black wire and strip both ends.
8. Attach the green, blue, black, and short black wire to the amplifier output connector (photo 8).
9. Connect the stereo amplifier as shown in the first diagram. The amplifier needs power so don't forget to attach power, plug it in, and turn it on according to the instructions that came with the amplifier.
10. Fire up your music and turn up the volume on the amplifier until the LEDs light up and flash to the beat of the music. If at this point it's still not working then check the wiring. If the wiring it correct then you may have damaged the LEDs or transistor during soldering or have a cold solder joint and probably should construct a new one.

Voila! The Musical Maker Mannequin is complete and should be working like the mine does in the videos!

In order to make the Musical Mannequin into the Musical Maker Mannequin, place a pair of goggles over his eyes, and Viola! the mannequin is all set to go!