Data Hacking

Chapter 10 — More Data Tricks
One of the best ways that I have found to synchronize a PC with an atomic clock is to use the
GPS signal. This offers several advantages over using the Internet:
You don’t need a connection to the Internet. You do, however, need a clear view of
the sky.
Each GPS satellite carries with it four atomic clocks. This means that the time signal
you will be getting is very accurate indeed.
In addition to the four atomic clocks, you can also take advantage of the capability to
average the time from three or more satellites, giving you access to between 12 and 24
four atomic clocks.
All you need to take advantage of this useful access to atomic clocks is a GPS and some software
that enables you to make use of it.
The best software I’ve found to carry out this task is called NMEATime by VisualGPS. This
software is shareware and it costs $20 to register. NMEATime is available for download from
the Visual GPS website at www.visualgps.net/NMEATime/default.htm. If you want
to just try it out before committing to buy (always a wise idea), a 30-day trial period is available.
NMEA is an abbreviation for National Marine Electronics Association. It defines the standard that
specifies how receivers communicate with each other and other devices (although there are
manufacturer specific protocols too). NMEATime can also be used to synchronize a PC’s clock
with Internet time servers.
Setting Up the Software
Before you can do anything, you need to set up the software:
1. Download NMEATime from the VisualGPS website.
2. Locate the download and run the executable file.
3. Follow the installation instructions. After NMEATime is installed, you can run the
application.
The best thing about NMEATime is its versatility. To get to the configuration screen of the
application, right-click on the clock and choose Properties.
You can also gain access to the application by right-clicking the icon in the system tray and
choosing Properties.
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