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illrrrrrrW - Free and Open Source Software
illrrrrrrW - Free and Open Source Software
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A. E. McGee, Jr. K5LLI<br />
281 5 Materhorn Dr.<br />
Dallas, TX 75228<br />
ee.<br />
PERF-BOA RD T E R M IN A L<br />
~~~~<br />
H<br />
aving successfully used the ty pe of<br />
Vector board with 3/32 in. perforatio<br />
ns and th e relatively large T9 .4 terminals<br />
in several projects, I decided to try th e<br />
ty pe with 1{16 in. perforations and th e<br />
small T28 terminals for more co mpa ct<br />
circuitry when recently building a frequen<br />
cy counter. The counter consiste d<br />
mainly of integrated circuits and a great<br />
deal of interconnectin g wiring, with up to<br />
fou r or five wires plus the Ie being<br />
connected to a single terminal. The T2 8<br />
terminals didn 't seem to be very well suited<br />
to my pur pose, so after some experimenting<br />
I came up with th is substitute . It is a<br />
simple pin-ty pe terminal tha t is inexpensive,<br />
easy to make and use, and better<br />
suited for so me purposes tha n the T28<br />
terminals.<br />
Making the terminals<br />
The terminals are made of l a-gage bare<br />
or tinned copper wire. Insulated wire is<br />
available at any hardware store, the least<br />
expensive being type TW. The plastic insulation<br />
is easily peeled off with a pocket<br />
knife. Clean the wire with fine sandpaper if<br />
it is tarnished or dirty.<br />
Cut the wire to the length desired for<br />
the terminals. I found that a 1'2 in. length<br />
worke d well for me. To easily cut a large<br />
number of terminals to exactly th e same<br />
length , simply drill a 5{64 in. (d iam eter)<br />
hole in any con venient material to a depth<br />
equal to the desired terminal length. Then<br />
you merely insert the wire, clip it off flu sh,<br />
and allow the terminal to dr op from the<br />
ho le.<br />
The l d-gage wire '" is a loose fit in th e<br />
1/ 16 in-diameter board perforations, so it<br />
must be exp anded slightly to make it a<br />
snug fit. This is done by knurling it lightly<br />
at the point where it will co ntact the<br />
board. Place the terminal on a small block<br />
of hard wood. Press down on the proper<br />
part of the term inal with the edge of a flat<br />
file. Move the file back and fo rth so as to<br />
roll the terminal beneath it. A few stro kes<br />
Th e term inals are knurled by rolling the m under<br />
a file .<br />
Th e term inals are eas ily inser ted with a simple<br />
tool.<br />
FEBR UARY 1971 83
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