Explorations in Engineering 2011
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Today's workshop was focused mainly on the hands-on, electrical engineering experience of actually building and testing circuits. Dr. Rhett started by comparing electricity to water: it has a current, fills containers, can overwhelm pipes and containers, and so on. From there, he began an explanation of the different components of the circuits, including their water-based counterpart. A battery, for instance, is a water source, albeit, for some of our electronics, too much of a waterfall to handle. We needed to build a circuit to regulate (and lower) the voltage to 5.1 volts for use with LEDs and in our final circuit. Resistors were introduced as a limit on the amount of water that came through at once, and as such, were integral to the voltage regulator circuit. Light-Emitting Diodes (LEDs) can be described as minature hydroelectric power plants, which create some other product (light, in this case) from the power of the moving water. We also worked with a Zener diode, which acted as another bucket, but one which simply caught the excess water.

With these parts explained, we were able to build two simple working circuits: a voltage-regulating circuit that output 5.1 volts all the time, rather than the 9 volts output by the battery, and a circuit which lit an LED. Dr. Rhett then moved to explain some other, more complex parts that we would be working with. He began with the capacitor, which he compared this to a bucket or container, which filled to a certain point, then let power through. This, when combined with an LED and 555 timer chip (which does exactly what it sounds like), causes a blinking light.

Finally, we moved into our final circuit: one which would essentially count, in binary, from 0 to 15. This used yet another new electrical part: the 7493 Counter Circuit, which, based on a current, would output, in binary, the numbers 0 to 15. This circuit actually used all of our previous circuits, including LEDs, the 555 Timer, and the voltage regulator, as well as new LEDs to show the output of the counter chip.