Part 1 of Essay
One of the fastest changing and most expensive fields, is that of technology. Our computers, printers, modems, and much more is being outdated faster than anything else in the world. Just as we buy a new computer that does what we want, the industry comes out with a new option on a smaller and better computer. There seems ....

Part 2 of Essay
.... and space (equivalent to that of a coffee-pot) to spare. Ultrasonic radar is now a small component for your computer, giving computer operators a chance to see low flying objects, household furniture, and even themselves on their PC screen. Just to impress a neighbour or friend is reason enough to build your own ultrasonic radar station. Similar to that of a Polaroid, ultrasonic transducers are used in this type of radar. A rangefinder emits a brief pulse of high frequency sound that produces an ech ....