Data Hacking

Chapter 2 — Building GPS Data Cables and Power Cords
The main disadvantage of this kind of cable is that it is more complex, and has many unused
ends and when in use need to be controlled, so as not to snag on anything.
Multi-Data/Power/GPS Cables
This is the ultimate GPS cable. It combines multiple GPS connectors, multiple device connectors,
and includes the features of a power cord. This cable should cover all eventualities and all
your needs. The disadvantage of this cable is that it can be a little bulky and cumbersome.
Making Your Own Data Cables
Now that you are familiar with the different types of cables that you can combine with your
GPS, it’s time to take a look at how to make some of them. I’ll begin by taking you through the
process of making a data cable. Specifically, this data cable is one for a Garmin eTrex GPS unit.
Materials You Will Need
To successfully build a data cable, you will need the following supplies and tools:
A suitable connector for your GPS (these are available from www.pfranc.com or
www.lynks.co.uk).
A cable with a 9-pin D connector on the end — any old serial port cable will do, such as
an old mouse or modem cable. Failing that, you will have to buy a cable).
Soldering iron
Solder
Pliers/wire cutters
Screwdriver (Crosspoint or Phillips)
Electronic multimeter or circuit tester (if you have a multimeter, it will have an “ohms”
setting — use this for circuit testing).
Cable Assembly
You assemble the cable as follows:
1. Take the wire with the 9-pin D connector at one end and cut off any connector at the
opposite end.
2. Cut the outer sheathing off the trimmed end and expose the inner core of wires, as
shown in Figure 2-5.
3. Strip the ends of the wires, as shown in Figure 2-6.
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