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Starting electronics
of one group you have made an electrical contact between
the two leads. In this way the component leads don’t have
to physically touch above the surface of the breadboard to
make electrical contact.
Differences lie between breadboards in the spacings and
positionings of the holes, and the number of holes in each
group. The majority of breadboards have hole spacings of
about 2.5 mm (actually 0.1 in — which is the exact hole spacing
required by a particular type of electronic component:
the dual-in-line integrated circuit — I’ll talk about this soon)
which is fine for general-purpose use, so the only things you
have to choose between are the numbers of holes in groups,
the size of the breadboard and the layout (that is, where the
groups are) on the breadboard.
Because there are so many different types of breadboard
available, we don’t specify a standard type to use in this
book. So the choice of what to buy is up to you. We do,
however, show circuits on a basic breadboard which is a
fairly common layout. So, any circuits we show you to build
on this breadboard can also be built on any similar quality
breadboard, but you may have to adjust the actual practical
circuit layout to suit.
Photo 2.1 shows a photograph of the breadboard we
use throughout this book, in which you can see the
top surface with all the component holes. Photo 2.2
shows the inside of the breadboard, with component
lead clips interconnected into groups. The groups of
clips are organised as two rows, the closest holes being
7.5 mm — (not just by coincidence the distance between
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