What is GPS?
GPS is acronym for Global Positioning System. It is actually
a constellation of 24 satellites providing navigational information
for the whole world. But when some people say "GPS",
they are usually referring to GPS-receivers ... small, portable
electronic devices about the size of a cellphone, similar
to the picture on the right, that receive information from
What does it do?
A basic GPS receiver interprets signals
from the satellites and tells you your position on this planet.
It usually gives you your position in coordinates (longtitude
and latitude), so, together with a map, you can have a fairly
good idea of where you are. Practically all GPS receivers nowadays
do more than just determine your position. Due to advances
in microprocessor technology, GPS receivers can now store thousands
of known positions called waypoints in their memory and are
able to provide a virtual "map" of destinations or points of
interests and it shows you the direction and distance to a destination,
it shows you the accurate time and lots of other stuff too.
Do I need it?
If you know the places where you are going
to very well ... probably not. But if you are venturing
into territory that is totally new to you and you are not able
to ask reliable directions or the place you are going to does
not have permanent landmarks, you will appreciate the fact that
a GPS receiver can lead you to "known" destinations even without
a map and compass. Oh, but even if you are already familiar
with places, a GPS receiver would serve as a very nice tool
for sharing locations and directions with other people.
How accurate is the system?
The satellite constellation that provides
the GPS receiver information is maintained by the U.S.Department
of Defense (DoD). GPS positioning, for general use, provides
25 meter accuracy or better. Since the general public
can access the signals from the satellites, the U.S. DoD has
introduced errors in the signals for security reasons.
The errors are referred to as Selective Availability (SA). SA
used to introduce an error of about 100 meters. SA
was turned off on May 2000 and has since then provided accuracy
as good as 10 meters.
So many GPS receivers on the market. Which one shall I buy?
The choice will ultimately be yours. But
as you begin your search, start by taking a look at the popular
models (the SporTrak Series from Magellan and the eTrex series
from Garmin) and compare their specs and choose the one that
suits you best. We currently use the Magellan GPS315 and
the Rino120 for this website. They are the only receivers
we have and we are very satisfied with them so far. We
are hoping to get our hands on other brands and models so we
can help you evaluate them.
If a company makes use of GPS receivers, do they need a
get a service provider for this in order for the devices to
work.? Is it similar to the internet that you have to get a
service provider before you can have access to the internet?
You do not need to get any service provider
for these devices to work. The "service" of the satellites are
provided by the US authorities and these satellites are transmitting
their signals freely for the use of the general public who own
GPS receivers. You simply need to buy a receiver and power it
up and you can immediately start your navigation, tracking,
waypoint marking, etc.
How can I make use of the downloadable waypoint files? Do
I need a GPS receiver to be able to use these files?
Our downloadable waypoints are gathered
and compiled in such a manner that it can be useful to trekkers
and travellers whether they own GPS receivers or not.
for more details on
how to use the waypoint files.
Questions? You can email
us your questions or you can join and post your questions
at the waypointsdotph egroup.
Alternatively, you can check out other more comprehensive
GPS FAQ sites on our Links Page