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GPS and GARtrip and me.
 My first
GPS receiver was a Garmin GPS 45. I bought it in May 1996, and I was happy
with it at first. I was very impressed about its functionality, compared to
its price. First I played with it just for my technical interest, then I found it very useful for my hiking tours. From
now on I did no hiking tour without detailed preparation. Spontaneous trips
became impossible, though.
After some time it was obvious that entering waypoint names and
descriptions with up/down keys is a pain. I looked for PC software. Thanks
to the Internet I knew there was more than Garmin's PCX5. At the same time
I felt that a true-to-scale printout of my track log would be nice, to be
printed on transparent paper and put in face of a map. And none of the
programs available did that. So I decided to write such a program myself. I
had some experience with Visual Basic 3.0, and I collected much knowledge
about coordinate systems on the Internet, see the acknowledgements below. I
did not know before what UTM is.
It took me four months to get it working basically. Then I decided
to publish it, but it took incredibly one more year to get it working well
for everyone. This fits to a general experience with development: When the
first prototype is working, 10 percent of the total work has been done, not
more. I received the first registration for version 108 on 29-July-1997.
In the mean time, beginning of 1997, I
bought a GPS12XL with GA27 antenna. This was a real big jump in
performance, compared to the old 45. Now it works well under trees, the
"no coverage" alert is seen rarely. When hiking, I leave the GPS
on all the time, in order to record the track log. Sometimes I just put it
into a pocket without GA27, facing upward as possible, but the reception is
sometimes critical then. Most times I fix the antenna on top of my
backpack. Then I may stow the receiver in any pocket without taking care on
its orientation. And how to fix the antenna? I glued a small piece of flat
iron inside the top cover of the backpack. Now I can put the magnetic
antenna outside, and it holds well and is easily removed.
GPS is a very useful aid for orientation. I learned reading a map
much more thoroughly than before. But there are restrictions in practical
use: for short walks, the track log is not accurate enough. Sometimes it is
not obvious which way is the correct one on a branching. Then I have to
take one way for some hundred meters watching the moving map, and it takes
a while to see that I'm wrong - not easy to explain to friends who expected
a miracle. Once I had a problem searching a ruin in a forest. My GPS said I
was close to it, but I could not find it. Later on I realized that I was
300 m above. I learned that I have to use my barometric altimeter in
addition when walking in steep terrain. In addition I use a cheap compass,
mostly in order to identify a visible mountain whose position I had stored
before. And finally, the trip odometer of the 12XL is of no use when
hiking. It suppresses slow movements, coming up with a much too small
readout. For distance measurement, I always use the track log analysed by GARtrip.
Later on, in the year 2001, I upgraded to a Garmin Etrex Vista. I hesitated very long because these funny
new Garmins are not better in every aspect. No
external antenna connection, no beeper, no waypoint description with time
stamp. But I found that the Vista is so small and lightweight that I can
carry it in a small holster on top of my shoulder while hiking. And for my
car I made my own reradiating
antenna out of the GA27. Works very well. What I still
miss is the waypoint description and the easiness of the menu control of
the good old 12XL. Anyway, I won't go back to it. The Vista is far better
in many aspects.
My next upgrade was early in 2004, to the new GPSmap60CS. It has all
good features of the old 12XL and the Vista in one unit, and in addition
its display is really outstanding; even the GPS reception is better. Then,
early in 2006, I went to the GPSmap60CSx - once again a tremendous increase
in GPS reception stability. Reception problems occur extremely seldom now,
but they are not impossible. This is a question of probability which never
will go to zero.I still use this Garmin device
today (April 2013) but for navigation I use the Nüvi
2595LM.
Bye Garmin: in the meantime, 2017, I’ve put the
60CSx away and I use my smartphone (Galaxy S4 with Locus Pro). Display is
much better, GPS reception is equal at least –
possibly due to additional use of Glonass
satellites. Locus Pro uses the barometric altimeter of the smartphone when
recording tracks; I searched for this feature for a long time. Finally,
power consumption of the smartphone with permanent GPS reception is decent
(about 8 % per hour). The only drawback is
lack of waterproofness.
Time goes on: now (2020) I’ve a Galaxy S10. Positions are much more
stable with it, again. This is possibly caused by the fact that besides GPS
and Glonass, it uses Beidou
and Galileo satellites. AND it is waterproof, so it’s well suited for
outdoor use.
Acknowledgement:
The very first and comprehensive collection of information on Garmin
GPS was done by Peter
Bennett.
The best information about GPS and coordinate systems was found at Peter
Dana's sites.
For Grid Systems, the best publication is "Map Projections - a
working manual" by John P. Snyder and "GPS in der Praxis" by
Hofmann-Wellenhof, Kienast,
and Lichtenegger (in German).
For the French Lambert grid, I got much help from people at ign, Paris, France.
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