from our immediate discussion, you can put that circular
saw away as we won’t be screwing down any of our
electrical components into a slab of pine. We’re about to
delve into some 21st century breadboarding.
If you’ve ever shopped for project parts at
RadioShack, you are already familiar with their
breadboards. RadioShack calls them perfboards. We’ll
call them breadboards. An example of a RadioShack
breadboard caught the attention of my camera in Photo 2.
The phenolic RadioShack breadboard depicted in Photo 2
is most likely designated as FR-2; FR in this case indicates
it is flame resistant and 2 is telling us that the perfboard is
made of synthetic resin bonded paper.
Other than being rated as FR-2, the phenolic
breadboard in Photo 2 is single-sided. That is, it presents
unplated copper pads on one side only. Since there is
only copper on one side of the board and there is no
plating on the copper pads, a plated-through pad cannot
exist on this breadboard. Thus, the RadioShack
breadboards are equivalent to a single-layer printed circuit
board (PCB) with no plated-through holes. These boards
work very well for general-purpose breadboarding of
standard leaded components. Some of the breadboards
can also handle the mounting of SMT components if you
choose a suitable copper pad arrangement.
If you don’t have access to a local RadioShack, you
most likely use mail-order electronic vendors such as
( www.jameco.com) or Mouser ( www.mouser.com) to get
your electronic parts fix. You will find a breadboard for
almost any application within the pages of their catalogs.
For instance, you’ll find a large selection of breadboards
constructed using epoxy resin. These glass/epoxy
breadboards are normally designated FR- 4. The number 4
signifies that the PCB material is composed of woven glass
reinforced epoxy resin. An FR- 4 breadboard posed for
Photo 3. The good news is that all of the basic techniques
associated with breadboarding can be performed equally
as well with an FR-2 breadboard as they can with an
FR- 4 breadboard. However, a breadboard with
plated-through holes does have its advantages.
wire is insulated, it must be stripped at both ends to
expose enough of the wire to attach and solder it to each
end of the electrical connection. Cutting, stripping,
positioning, and soldering wires make up the bulk of
breadboarding work. All of the mail-order electronics
outlets and local RadioShacks offer electronic hand tools
to help you with manipulating breadboard wiring. I have
also found that local home centers stock high quality wire
cutters, lead cutters, and pliers that work well in the
breadboarding environment. Since good solder joints are
a must for point-to-point electronic assembly, I suggest
investing in a good quality soldering station. Check the
pages of Nuts & Volts and you’ll find a number of vendors
that can help you put a reliable soldering station on your
bench. The bottom line in tool selection is quality. I know
from experience that when those cheap lead cutters go
dull in the middle of an important breadboarding project,
you’ll wish that you had spent that extra couple of dollars
for a higher quality tool.
I’m not going to insult your intelligence by detailing
the process of mounting a component on a breadboard
and wiring it in. However, I will pass along some
• Rats nest wiring techniques insure breadboarding failure.
• Poor component layout insures breadboarding failure.
• Sloppy soldering techniques insure breadboarding failure.
• Never begin a breadboarding project until you have
all of the components in hand.
• Route your breadboard wiring as if you were
■ PHOTO 3. This FR- 4 breadboard consists of 0.046 inch
diameter plated through-holes, which are dispersed on
0.1 inch centers. The through-hole solder plating enables
electrical continuity between both sides of the
breadboard at every hole. Thus, this breadboard can be
considered as double-sided with plated through-holes.
The goal of breadboarding is to mount
electronic components on a supporting
substrate and make all of the necessary
electrical connections that result in a functional
electronic device. In most cases, a length of
wire is used to make an electrical connection
between components mounted on a breadboard. Before the wire is installed in the circuit
path, the wire must be cut to length and if the
■ PHOTO 2. The copper pads on the other side
of this perfboard are not solder-plated. So,
you’ll need to clean the copper pads with a
Scotch-Brite pad before attempting to do any
serious breadboarding with this perfboard.
December 2008 63