Volts reader, you probably
know by now that I enjoy
building small stripboard
circuits, especially PICAXE
programming adapters. (If not,
as a TankBot owner you might
want to check out the
bi-monthly “PICAXE Primer”
column in Nuts & Volts –
several of the projects we have
done there could easily be
adapted to robotics experimentation.) Since a programming
adapter can save some space
on a breadboard circuit (or any
circuit for that matter), I
decided to make a small
programming adapter (Prog03)
specifically suited to the
TankBot. Not only does it free
up more breadboard real estate in our
current TankBot project, it will also
come in handy in many future projects,
as well. The April 2008 installment of
the PICAXE primer in Nuts & Volts
presented the details of stripboard circuit
construction and there isn’t enough
space here to include all that information.
After reading the following section, if
you decide you want to construct the
Prog03 adapter it would be a good
idea to check out that issue of N&V.
I used a piece of software called
“LochMaster” (German for “Strip
Master”) to design the top and
bottom stripboard layouts shown in
Figure 3. As you can see, it’s a simple
board that includes the three resistors
(180 ohms, 10K, and 22K) needed for
the basic PICAXE programming circuit.
The black component on the right is a
three-pin male header that I’ll describe
shortly. What you don’t see in Figure
3 is the female DB9 connector that
gets soldered to the left edge of the
board. I didn’t include it because
there was no suitable graphic in
LochMaster. However, when we get to
the actual construction of the Prog03
adapter, I’ll include photos that will
make clear what is required.
Except for the female DB9
connector, all of the necessary parts
(including the stripboard) are available
on my website ( www.JRHackett.net).
Figure 1. Modified IR Echo Project Schematic.
The required female DB9 connector is
the type that includes what are called
“solder cups,” which means that wires
can be directly soldered to the back end
of the connector. If you don’t already have
one on hand, this type of connector is
commonly available (e.g., www.allelec
tronics.com part #DB-9S or www.
sparkfun.com part #PRT-00110).
There are a couple of ways to cut
the strips as needed on the bottom of
a stripboard. The details are covered
in the PICAXE Primer article
mentioned above, but for the Prog03
board all you need is either a 1/8” (or
5/32”) drill bit or a sharp hobby knife
(and a steady hand). The easiest type
of cut to make (and the only one
required for the Prog03 board) is one
that can be done at a hole in the
board (as opposed to cutting the
trace between two holes). To cut a
trace at a hole, all you need to do is
to hold the drill bit between your
Figure 2. IR Echo Circuit Installed on Breadboard.
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