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

Linear Electronic Circuits
253
manufacture is a learned technique, and like any technique, there are
several “correct” ways of going about it and many “wrong” ways of
accomplishing disaster. In this section, I’m going to detail several methods
that can be successfully used by the hobbyist. With a little practice,
either of these methods should provide excellent results. The 12-watt
audio amplifier described in the previous section is an excellent “first”
project for getting acquainted with PC board fabrication, so I included a
set of PC board layout illustrations in Fig. 8-9. See Appendix C for the
full-size set to be used in your project.
To begin, you will need to acquire some basic tools and materials. If
you are a complete novice regarding PC board construction, I recommend
that you start by purchasing a “PC board kit,” such as the one illustrated
in Fig. 8-10. Typically, such kits will contain a bottle of etchant (an
acid solution used to dissolve any exposed copper areas on the PC board),
a resist ink pen (a pen used to draw a protective ink coating over any copper
areas that you don’t want dissolved by the etchant), several “blank” (i.e.,
unetched) pieces of PC board material, and some miscellaneous supplies
that you may or may not need. In addition, you will need a few very
small drill bits (no. 61 is a good size), an electric hand drill, some finegrained
emery paper, a small pin punch, a tack hammer, and a glass tray.
If you want to make a PC board of the Fig. 8-9 artwork by hand, the
following procedure can be used. Begin by observing the illustrations
provided in Fig. 8-9. Figure 8-9a is commonly called the silkscreen layout.
It illustrates a top view of the placement and orientation of the components
after they are correctly mounted to the PC board. Figure 8-9b is
another top view of the silkscreen, illustrating how the bottom-side
Figure 8-10
Illustration of a typical
PC board fabrication
kit.