■ PHOTO 6. The four-position diskette drive power
connector is something we’ve been plugging into for
years. You can get this power connector and its mating
plug from Jameco. The center power receptacle is
actually a Type-B USB connector. The business end of a
wall wart power cable mates nicely with the industry
standard 2.5 mm male power jack.
which of the diskette drive power interface pins you
connect, you’ll get + 12 VDC or + 5 VDC. So, be careful.
Believe it or not, the Type-B USB connector is 0.1 inch
friendly. Two of the USB connector’s four pins — which sit
on 0.1 inch centers — carry + 5 VDC (pin 1) and ground
(pin 4). I had to break out the Moto-Tool to mount the
2.5 mm male power jack. This power jack allows you to
power your breadboard from the wall wart of your choice.
How I Do It
There’s a breadboard behind every PCB I present in
my Nuts & Volts and SERVO Magazine articles. Needless
to say, I’ve done my share of breadboarding. I use 30
AWG Kynar wirewrap wire to make my breadboard signal
connections. The Kynar insulation is easily deformed by
the direct heat of a hot soldering iron. Thus, it is possible
to accidentally overheat it and compromise the wire’s
insulation by creating a void. It’s uncanny, but those
insulation voids always seem to create shorts to nearby
exposed connections on my breadboards. If things on
your breadboard are squirrely and you can’t find a logical
reason why, check for wires that are stuck together or
stuck to a neighboring solder connection. The insulation
voids usually occur at those points.
If the breadboard requires a power and ground bus, I
complete the component layout and then route the power
and ground busses on the breadboard copper using 22 or
24 AWG tinned copper bus bar.
Working smart also includes being smart when it
comes to tool selection. I consistently use the following
• PanaVise Electronic Work Center with 315 Circuit Board
• Variable Speed Dremel Moto-Tool
• Metcal MX-5005 Soldering/Rework System
• Crescent Hand Tools (Home Depot)
Over the years, I’ve developed breadboarding
methods and habits that work well for me. As time
passes and you do more and more breadboarding, you
will benefit from your experiences, as well.
By the way, if you’re having trouble finding that FR- 4
plated through-hole breadboard I’ve been talking about in
the catalogs, stop looking. I’ve supplied a downloadable
ExpressPCB file that will allow you to make one (or a few)
of your own ( www.nutsvolts.com). See you later ... I’ve
got some breadboarding I have to do. NV
Order online at:
Development Tools for PIC® MCUs
microEngineering Labs, Inc.
Phone: (719) 520-5323
Fax: (719) 520-1867
Colorado Springs, CO 80960
With Accessories for $119.95:
December 2008 65