Colin McDonald writes:
>when you say perf board what do you mean?

        Perforated board has been around for decades as a means for
building hobby or custom projects.  It comes in lots of different
qualities and configurations.  It looks like peg board except the
holes are closer together.  The kind you want for IC sockets has ten
holes per inch such that they form lines of holes spaced 1-tenth of an
inch apart.  It feels a lot like a speaker grill except that it would
make a very expensive speaker grill.

        There is also perf board with coper strips along the holes.
The strips go from one end of the board to the other and you have to
cut them.  One can also solder sockets and other things to that kind
of board.  I usually do not use it because it is hard to recycle in to
another project.

        Some perf board has no strips, but does have coper eyelets
that one can solder to.

        Again, this makes recycling old projects harder so what I use
is the board with no coper on it.

        There are older types of perf board around with hole spacing
of 5 per inch or so.  These holes are too far apart for IC sockets,
but they are fine for power supplies or places where there aren't
going to be any very close components.

        You need a wire-wrapping tool.  Unless you plan to become a
factory operation, the manual wire wrapping tools sold by Radio Shack
and a few other companies work well.  The tools look like a little
screwdriver or nut driver with a hollow tube coming out both ends of
the handle.

        One hollow tube is shorter and fatter than the other.  The
long thin end is for wrapping and the shorter fatter tube is for
unwrapping.

        If you could see in to the open end of the wrapper, you would
see that there is a key hole-shaped insert in the end.  The round part
is right in the center and there is a hole the size of the 30-gauge
wire off to the side so that when you stick some stripped wire wrap
wire in to it, it only goes in as far as the stripped part and stops
right there.  Then, you lower the hollow part down over the IC socket
pin with the pin going in to the center hole.  You can then make the
wrap by carefully turning the tool until all the stripped wire is
wrapped around the pin.  You'll get to where you can feel it turn a
little easier when it isn't wrapping any more.

        There are actually two kinds of wrapping tools.  The newer
ones from the last ten years or so have that little key hole a little
further back inside the hollow tube so that it wraps a couple of turns
of insulated wire along with the bare wire for mechanical strength.

        The other end of the tool can usually catch the end of the
wrapped wire and unwrap it when you are either tearing down a project
or modifying it.

        The older wrapping tools don't do that extra wrap of insulated
wire so you have to be very careful not to leave any bare wire leading
in to the pin because it could get pulled over against a neighboring
pin.

        Finally, you can buy or at least used to be able to buy
perforated boards from Radio Shack that have the .1-inch hole spacing.

        If you get a chance to, find someone in your local radio club
who might already have some of this stuff to show you so you will know
what it really looks like.

        If you decide to try to program Picks, you will need to learn
assembly language and or C because that's the way to tell these chips
what to do.

        Start out simple and don't expect to build an inertial
guidance system for a F16 fighter right off the bat.  If you try too
much, you'll just get discouraged.  All of us have ruined stuff from
time to time, but the name of the game is to go carefully and check
your work.  If you do that, you will be surprised how little damage
you do and you will have some fun.

        A few other thoughts.  Most duel inline package IC's which are
the kind that have pins that go through the board, have a little notch
cut in to one end of the IC.  That is the end where Pin 1 is.  If you
hold the chip so that that notch is at twelve o'clock, there is a
vertical line of pins on the left and another on the right.  Pin 1 is
in the upper right corner as you look at the bottom of the chip.  If
there 8 pins on a side, Pin 8 is the lower right opposite Pin 9 which
is the lower left.  You count down the right side and up the left so
that a 18-pin chip has Pins 1 through 9 going down the right and then
10 through 18 with 18 being at the upper left corner.  You will
certainly fry it well if you flip it wrong way around.

        Tubular electrolytic capacitors often times have a lip or band
around the positive end and nothing around the negative end.  It's the
ones that have both leads coming out the bottom that you have to test
to make sure you don't have it wrong.

        Good luck.

Martin McCormick WB5AGZ  Stillwater, OK
OSU Information Technology Division Network Operations Group