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This was by far the coolest machine I came across when deciding what to build for my final project, even though it really is the most useless machine in the world. I remember seeing this concept when I was a kid and always wanting to build one of my own. It is a very basic idea, you flip a switch on and a motorized arm comes out of the box to turn itself off. This involves a micro server or geared motor, two switches, and a battery pack. The switches consist of a toggle switch and a micro switch. The micro switch will be wired to work opposite of how it usually works and the toggle switch starts in the reverse direction. When the machine has no power, the micro switch is being held in the off position by the servo arm and it isn’t until you flip the toggle switch that it is released, causing the arm to rotate toward the toggle switch. When the servo arm turns itself “off”, it is really causing the motor to reverse and head back to rest on the micro switch. That is when the machine is fully powered down. The build that I decided to go with is a more complex one, but you will be much prouder of the product once finished. I was not able to get mine to work how I wanted it to and I will explain the problem later, but I hope that you can take my work and improve upon it.

Including digikey part numbers:

- Servo 900-00005-ND
- Battery Holder 4-AA Cells BH24AAW-ND
- NE555P Chip 296-1411-5-ND
- C1 0.1 uF Capacitor 478-1831-ND
- R1 220K resistor CF1/4220KJRCT-ND
- R2 27K resistor CF1/427KJRCT-ND
- R3 15K resistor CF1/415KJRCT-ND
- D1 1N4148 Diode 1N4148FS-ND
- DPDT Toggle Switch 450-1533-ND
- SPDT Micro-Switch EG4544-ND

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