Look at the printed circuit board (PCB)
and be sure you understand how it should be oriented. Almost all of
the components will be placed on top of the board while it is oriented
as shown at
left. On the robot, this side of the board which will face downwards,
hanging beneath the robot platform. The last component you will
solder--the LED--will be fastened on
the opposite side so you can see it through the translucent robot platform.
Notice that the board is "double sided" meaning
that it has lines of metal printed on both top and bottom. These metal
traces are the "wires" which will conduct electricity. The
holes are "plated through" so
metal (and electricity) pass through the board at those points.
The board is also coated with a protective
covering, so the metal is only exposed in and around the holes. Some
of the larger holes have no metal traces, since they will be used for
mechanical connections, not electrical connections.
