Tab Electronics Guide to Understanding Electricity ... - Sciences Club

Getting Started
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zines (often called “advertisers”). For noncommercial individuals, these
ads are usually placed free of charge. If your interests happen to be in
the digital electronics field (computers and accessories), a typical ad
might read as follows:
Electronics experimenter interested in purchasing obsolete or nonfunctional
computers or computer equipment. Call (your telephone number).
Hypothetically, if you placed an ad such as this in a local shopper magazine,
and someone called you in response to that ad, try to keep a few
points in mind. There are many obsolete and useless computers in
homes and businesses today. In many cases, obsolete or defective computers
are not even supportable by the companies that manufactured
them. The person calling you probably has only two options available:
sell the computer stuff to you, or throw it away. You shouldn’t pay any
more than “scrap” value for equipment of this sort. This is just an example,
but the technique should work equally well in any personalelectronics
interest you might have. But I have one word of caution; do a
little research, and know your market before you try this technique.
What to Salvage
Many junked electronic items will contain subassemblies that are valuable
to the electronics hobbyist and experimenter. Old CD players, computers,
and VCRs often contain good power supplies, usable for other projects,
or even for lab power supplies. (Two of the power supplies that I use the
most often in my lab came from junked equipment.) Junked stereo systems
might contain good audio power amplifier subassemblies. These
are only a few examples. The point is, always check out the value of
equipment subassemblies before tearing everything apart to salvage components.
Any person interested in robotics will find a wealth of electromechanical
items in old VCRs, including motors, gears, pulleys, belts,
limit switches, and optical sensors. Junked CD players often contain
functional laser diodes for experimentation or making laser pointers (be
very careful to protect your eyes if you experiment with any kind of
laser, or laser diode). Junked computers might contain good floppy
drives, hard drives, or memory chips. Commonly used electronic hardware
(fuse holders, line cords, switches, etc.) is found in almost all electronic
equipment.