GPS Buyer Guides
Which GPS Receiver Should I Buy?
If you are like most people searching for GPS receivers, you are probably
asking "Which receiver should I buy?" So you know you need a GPS receiver.
It can be difficult to sort through the array of features, types, and
brands that are out there. In this section, I will try to provide a
framework or a method that can help a prospective GPS user purchase a receiver.
How it works
A GPS receiver is a unit that uses advanced triangulation techniques to
compute your location. The receiver gets transmitted information from
satellites and uses transmissions from 4 or more satellites to locate your
position. It can also compute speed and direction data. The unit also
offers a display of the information in a form that a customer finds
helpful (usually a handheld device). The format that the data is
displayed in is one of the biggest items that differentiates different
GPS receivers. All data from GPS receivers are calculated from
satellite-transmitted data, not from a compass, speedometer, or altimeter.
The altitude data that a GPS receiver outputs can often be off by 30
meters or so and can fluctuate. Some GPS systems have a built in compass,
but other, inexpensive ones do not. When you are in the wilderness, a
compass and a altimeter are good compliments for a GPS receiver.
There are many GPS receivers on the market. However, one of the most
important factors in determining the right GPS receiver to buy is the
application that it will be used for. If you are an avid mountain hiker,
you would probably want a GPS that was extremely lightweight, contained
detailed altitude, and had other tracking features that would allow you
to plan a hike. However, if you are a real estate agent and purchase a
GPS for use in the city, you might want a larger screen that superimposes
street maps to allow you to find your houses quickly. Even if you buy a
GPS for one purpose, it is likely that you will find additional uses for
your receiver once you have it. It is always better to buy a GPS with a
few more features than you think you will need. One thing that is helpful
in determining what you will do with a GPS is to understand all of the
things that a GPS receiver can be used for.
This is one area that you need to be careful about. Most GPS systems will
not work under a thin layer of water since it is difficult for the signal
to go through. A 12 channel parallel unit is almost a no-brainer.
Without this type of GPS, you may have difficulty receiving the signal
without an unobstructed view of the sky. Even then, you may have to wait
around for a couple of minutes. You will also want to make sure that the
GPS system has the screens that you want.
If you have a computer, you may want to get a GPS that has a computer
interface to allow you to transfer data back and forth. Most people want
a GPS system that can work standalone, but has the computer interface.
A standalone unit is able to function without a computer, but a unit that
doesn't have a display requires a computer to use the information..
Questions to think about
In addition to the items mentioned above, you will want to answer several
questions before you are make your purchase decision:
How long does the battery last?
Does it have the features that you need?
How easy is it to locate the data you need?
How's easy is it to configure or customize?
If you want a computer interface then does it support one?
What kind of upgrades are available?
Can you get the programs you want to work on the unit?
How easy to read is the text on the screen display?
Does the data have all of the formats you are interested in (grid systems, datums)?
Do you want or need internal maps?
Do you need it to be waterproof?
Do you like the interface?
How available are accessories, mounts, cases?
How accurate are the built in maps?
Do I need dpgs or WAAS?
You could probably get the answers to most of these questions on the web
or through the manufacturer. There are a lot of good resources out there.
Best of luck on your search!