Geek Clock- Makes a unique gift for the geek in your life! Custom made by artist Rob Power, this clock represents a twist on the old analog clock. Plastic case with binary numbered dial. Dimensions (Overall): 8.81 Inches (H) x 8.81 Inches (W) x 1.51 Inches (D) The “geek” Clock Digital electronics involves circuits and systems in which there are only two possible states. These states are represented by two different voltage levels: A HIGH and a LOW. In digital systems, combinations of these two states are used to represent numbers, symbols, alphabetic characters, and other types of information. The two-state number system is the binary number system and it uses the digits 1 and 0 to represent a HIGH and a LOW condition. Logic gates are circuits that are used to electronically express the result of a basic logic operation. The four basic logic operations are: NOT, AND, OR, and EXCLUSIVE- OR. These operations form the entire basis of operation of modern computers. The circuit in the center of the clock is the typical schematic for a single gate in a Texas Instruments SN5400 quadruple 2- input positive- NAND gate. This particular type of logic gate is important because the design of the NAND gate lends itself to utilization as a “universal gate”. That is, various combinations of this particular logic gate can be used to construct and perform any of the four basic logic operations. Directly below the schematic is the “truth table” for this particular gate. It shows that the output (Y) will remain LOW in all cases except when both inputs (A & B) are LOW. In terms of scale, if you were to make a Pentium processor using nothing other that this type of circuit, you would need to fit approximately 280 million of them in an area about the size of your thumbnail. The numbers around the dial of the clock, if you haven’t guessed by now, are 4- bit binary numbers representing the decimal numbers 1 thru 12.