The Singing Keyboard Prank

Step 3 Switch work - The Transistor

We now need to replace the metal switch with your transistor. You don't need to know anything about transistors for this project, just make sure you purchased an NPN type transistor and follow along.

Metal Switch Parts
The element already has a switch, that we'll be modifying for our purposes. The bendable metal part of the switch I’m calling the metal tab (or switch arm), and thing it connects to, or touches, I’m calling the contact area. You can remove the paper or plastic thing that the card used to make contact when the card is opened.

Transistor Work
Take the transistor and bend the center pin back slightly. Then slide the transistor onto the musical element switch area with the outer pins on top and the center pin on the bottom .

Now make sure that one of the outer pins is resting on top of the metal tab and the other outer pin on the contact area. (see the picture with notes)

Lastly, using your needle nose pliers bend the metal switch tab back over the transistor pin and make sure it holds it tightly. Now solder the other other pin to the switch contact area. (see second picture with notes)