Data Hacking

66 Part I — Hardware Hacks
1. Hold the antenna as far away from your body (and other human or animal bodies) as
possible and away from other electrical devices, as these can all degrade the accuracy of
your receiver.
2. If your GPS uses a patch antenna, keep it as close to horizontal as possible.
3. If your antenna is a quad-helix antenna, keep it as close to vertical as possible.
4. Whatever type of antenna you use, keep it as dry as possible — a coating of water
droplets will severely affect performance.
External Antennas
One problem with holding your GPS in a nearly vertical or nearly horizontal orientation is
that it can quickly become uncomfortable and cause you to start walking oddly. If you are in a
vehicle, then the problem isn’t one of orientation but actually getting the signal to the GPS, as
most receivers find it hard to get a lock to the satellites when inside a car or boat. A far better
idea is to place the antenna away from the GPS receiver. Some GPS receivers come with either
a removable antenna or a socket that enables you to hook up an auxiliary external antenna to
the device.
Figure 4-6 shows a Garmin III GPS receiver with the original antenna removed.
FIGURE 4-6: A Garmin III GPS receiver with the antenna removed