Unstrument Workshop: Step-By-Step Instructions for Building the Circuit

Prepare the Power Columns on the Breadboard

Connect the 2 positive columns (+) on either side of the breadboard together
 
Connect the 2 negative columns (-) on either side of the breadboard to together 
 
Connect the red (+) wire of the battery clip to one of the holes along the positive power columns. 
 
Connect the black (-) wire of the battery clip to one of the holes along the negative column.  
 
DO NOT CONNECT THE BATTERY YET! 
 
Why we do this:  These connections make it easier to connect components to the power source (battery) since they can be connected to either side of the breadboard.
 
Insert the 555 Timer Chip and Connect it to the Power
The 555 Timer chip is the first component we insert into the breadboard because it is the brain of this circuit!  All the other components connect to it and help it carry out its job.  
 
Insert the 555 Timer into the middle of the breadboard – 4 legs on either side of the vertical line break.  Push it into the board until you hear it click into place.
 
The following steps connect the 555 Timer chip to the power to make sure that it has the power it needs to work:
 
Locate the pin orientation of the 555 timer.  Look at the diagram [hyperlink to pin out diagram] or find it here:
http://upload.wikimedia.org/wikipedia/commons/c/c7/555_Pinout.svg
 
Connect pin 1 to the negative column (-)
 
Connect pin 4 to the positive column (+9 volts)

Connect pin 8 to the positive column (+9 volts)
 
Next, we need to insert the components connected to the chip.  Remember: make sure to respect the pin orientation! Insert the 0.01uf capacitor between pin 1 and pin 2
 
Use a jumper wire to connect pin 2 and pin 6
 
Connect the positive lead of the 100uf electrolytic capacitor to pin 3 and insert the negative lead into an arbitrary row that is not occupied by any other components

Attach the speaker to the negative lead of the electrolytic capacitor by connect one of the terminal leads to the same row 
 
Connect the other terminal lead of the speaker beside the row with the capacitor and use a jumper wire to connect that row to the negative column 
 
Attach the alligator clips to the breadboard by connecting the terminals to 2 unoccupied rows on the breadboard 
 
Use jumper wires to connect the alligator clip terminal to pin 6 and pin 7
 
Insert the 10k resistor between pin 7 and pin 8
 
The next steps help us test out the Circuit
CONNECT THE BATTERY! (Hint: if your circuit is properly built, you should hear the speaker make a faint click when you connect the battery)
 
Test your circuit makes by touching the metal parts of the alligator clips simultaneously – If you hear sounds when you touch the metal
CONGRATULATIONS! Your circuit works!
 
If your circuit is not working – DON’T WORRY!  This happens all the time – even to expert circuit builders...Follow the troubleshooting guide below.
 
Experiment with your Circuit
Test out what kind of sounds you can make by attaching different kinds of conductive materials between the alligator clips
 
Connect the leads of a photocell to either alligator clip (wave your hands around in front of it.  What happens when you block out the light?
 
Move the clips along pencil markings to hear what happens
 
Have a friend hold one alligator clip while you hold the other one –What happens when you touch each other’s empty hand?
 
Try testing out different objects to see if they make sounds

REMEMBER!!! – You must be touching the metal part of the alligator clip in order to make sounds.  The plastic insulation does not conduct electrical current so it will not make sounds.
Also: If you are not using your circuit – detach the battery so it doesn’t run out.

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