The Lowrance GM-100 Mapping GPS Receiver> Product Review
                        By Ira Wilner

Here are my impressions of the Lowrance GlobalMap-100 GPS receiver.

It is sized like an elongated bar of soap.  And with 4 AA batteries
has quite a heft.  But it is significantly smaller than the MicroLogic
ML-150 and of course dwarfed by the large Eagle AccuNav Sport.

Battery compartment cover comes off providing full battery length access
for easy extrication of oversized AA cells or the installation of an
NiMH rechargeable battery pack.

There are two dust covers over two recessed connectors.  One is a
multi-pin data I/O and power port while the other appears to be an MCX
or similar push-on coaxial RF connector for an external, passive only,
antenna.  That, so far, is the only significant let down.  The RF port
is unpowered.

Positioned on the back of the case directly behind the patch antenna,
these ports will not allow the receiver to lay flat on your dashboard if
you plan to use external power, a DGPS receiver or an external antenna.
The optional mounting bracket accessory (MB-2) allows for it. As
does the foam wedge for tabletop mounting.

The patch antenna is built into the upper end of the case and has
approximately a 30 degree angle to help it see the sky with the display
tilted somewhat towards the operator.  This helps make the unit
mechanically rugged.

The membrane keyboard is located on the lower end of the case, with the
LCD display dead center, much like the Garmin GPSIII.  One hand control
can be achieved by using your thumb as the actuator.  But it does not
afford a secure grasp of the case.  Thus it is important to attach and
use the supplied wrist strap as a safety belt!  The lanyard, which
attaches to the top rear of the case is extra long to reach your wrist
which will be below the unit.

The GM-100's keyboard is very responsive.  It behaves as though
interrupt driven. It responds to your keystrokes immediately.  This is
in sharp contrast to the ML-150 which appears to be polled and can
become totally unresponsive when its microprocessor is busy.

The keys are as follows:

PAGES, provides access to the screen select menu.  As you highlight a
selection using the up/down cursor keys the screens instantly change and
are visible behind the menu.  Pressing EXIT removes the menu, allowing
normal use of the new screen.

MENU, opens menus for setup and control of the GPS unit or special
choices for the currently visible screen.

WPT, opens a large waypoint menu which permits you to save a new
waypoint, go to a waypoint (navigate), create a waypoint from keyboard
input or by projection from an existing waypoint, or edit an existing
waypoint. In addition you can select position averaging mode.  The
display will count the number of sample points accumulated while showing
you the wondering track or ink blot.  When you have enough, pressing

ENT, enter, records the average of all of the sample points.  You can
average over any length of time, but you must be there to terminate the
process.

PWR, powers up the receiver and shuts it down if you hold it pressed for
three seconds.  Briefly pressing the key will toggle the backlight on or
off.

ZOUT, ZIN are direct zoom control buttons for maps.  Pressing them both
at the same time will generate a nearest waypoint table and display it.

The super twist LCD display is similar in resolution to the larger
Lowrance/Eagle charting displays but has half the width and thus a bit
more than half the horizontal pixels of those larger receivers.  There
are at least 3 gray scale levels and more than five backlight intensity
levels.  Electrolumnescent technology is used to provide an easy to view
blue green backlight.  The keys, however are not illuminated.  Operation
in the dark requires memorization of the keys and tactile touch.

You can choose the on time for the backlight all the way up to
constantly on.  With firmware version 1.2 the backlight will automatically
stay on when operating on external power and will revert to timed shutoff
when powered up on internal batteries.  One caveat however.  The
display will not automatically switch to timed shut down upon loss of
external power.

While the ML-150 will display a wall plug icon when on external power,
the only indication from the GM-100 that it is not using its internal
batteries is a full scale reading on the battery capacity bar graph.
Though less intuitive, I miss the voltmeter readout of the AccuNav
Sport.

Virtually every GM-100 screen can be customized!  Any combination of
large or small digital data boxes, analog sweep second hand clock, and
plotter/charting maps can be selected.  Windows with a vengeance, so to
speak.

The compass rose navigation screen includes a miniature plotting map in
its center showing you some tracking detail, like a contrail or wake.
But like most GPS's, the compass card or ring display rotates with jerky
motion. Am I the only one who appreciated the wonderful simulation of a
floating compass display with smooth fluid movement, like that in the
AccuNav Sport?

The distance to go box reads in miles and then switches to feet as you
approach your target waypoint!

The basic built-in worldwide and North America background maps are quite
detailed having all major Interstate Highways and many numbered state
roads and the smallest rivers.  Yes, the mapping data seems to be
waterway heavy.

The IMS Smartmaps on CD-ROM add additional county roads and just about
every brook and stream!  Street level details are omitted.  The maps are
no substitute for SA-5 or paper street maps.  However, highway
intersections including the on and off ramps are all there as are the
names of virtually all the towns in my rural state of Vermont.  (But read on.  The
newest CD-ROM release from Lowrance with MapCreate software provides
exceptional rural street and road detail.)

Coastal marine navigation aides for North America are presently broken
into two 1 megabyte segments.  Thus the unit can hold data for both
coasts at the same time.  The ML-150 comes with a built-in database for
either coast but not both.  The databases also include the bigger lakes
and rivers.  In New England this includes Lake Champlain, the Hudson
River and the lower Connecticut River.

The ML-150's database holds more details about the nav-aides, such as
official database index number and distance for viewability or
audibility and the type of sounder.  The GM-100 only provides the
visible daytime color, identification number, night light color and
flash rate.  But it also uses different icons to indicate buoy, light or
sign type markers.  Lowrance did not want to clutter the map with more
details while the MicroLogic, not being a mapping GPS, shows the
nav-aide details on a separate text screen.

Similarly, the ML-150 has a screen for displaying the distance between
any two selected waypoints, while the GM-100 relies upon point and
shoot. The GM-100 allows you to select point "A" and then move the
cursor to point "B" and get the azimuth and distance from A to B
anywhere on the map.  Both points do not have to be visible at the same
time and you can zoom in or out as necessary to locate the point of
interest.  You can also navigate to any point selected by the cursor
even though it might not be a stored waypoint!

The latest firmware for the GM-100 V.1.2, posted on the Lowrance website
for download, turns off the nav-aide labels on the maps until you touch
their icons with a cursor. This helps to reduce screen clutter.  But it
has been reported to be buggy with screens set up to show two maps.  A
corrected version is on the way.

The ML-150 can generate a list of the closest nav-aides to your present
location showing coordinates azimuth and distance from you. The GM-100
simply places the nav-aides on its maps.  You can then zoom out as far
as necessary to find their icons and descriptions. By placing a cursor
over the icon the map will show you the coordinates, azimuth and
distance from your present location.  So, the GM-100 has essentially the
same capability as the ML-150.

Uploading time from CD-ROM to the GPS receiver depends upon the maximum
serial port speed that you can achieve.  The GPS data management
software automatically detects the speed of the receiver's serial port
and sets the host PC's port accordingly.  You only have to set the
serial port speed in the GM-100 which can be as high as 115.6kbd!  At
115.6kbd, a one megabyte "SmartMap" file takes a little over 5 minutes to
load.

The PC based waypoint management software is basic, not having the
ability to sort the list.  The only serious PC software bug I found was
the inability to choose an IMS map by clicking on the map of the entire
US broken down into IMS map segments.  Instead I had to manually scroll
through the map segment names and choose them.  It made selection of
the desired coverage area more tedious.  Apparently there are
compatibility problems with some of the the 16 bit runtime files and PC
hardware/software.  Most users have not run into this problem.  I must
have been specially blessed!  :-)  I had no problems after upgrading my
operating system to Windows-98.

The GlobalMap-100 itself will sort and create an alphabetical waypoint
list that you can use to pick waypoints for insertion into routes.
Unfortunately you cannot do the same with the "nearest waypoint" list
which makes it less useful.

External power input is rated for 5-30 VDC, a very substantial range.
For those who have 6 volt electrical systems or consumer style camcorder
battery belt packs, you now have access to a long run power source!
Measured current draw at 6 vdc is 173 ma.  With backlight at half
brightness the current demand goes up another 15 ma.

The receiver is moderately power hungry, though not nearly as bad as the
AccuNav Sport or MicroLogic.  Lowrance claims significant battery life
enhancement in power save mode (20 hours).  But, like all such features
which reduce the position fix update rate, the ability to track under
poor sky coverage may be degraded.

I tested the power save feature and found it to be remarkably usable!
Even in PS mode, the satellite status screen still showed rapid
re-acquisition of birds!  There was a greater propensity to lose
navigation lock in this mode, but it did surprisingly well under
moderate tree canopy near the summit of Putney Mountain, approximately
1,400 feet above mean sea level.  It only lost lock once in a 1/2 mile
trek under continuous tree cover.

There are audible alarms for anchor watch, cross track error, loss of
lock, arrival, overshooting, alarm clocks and low battery.  In the same
tradition of the AccuNav Sport, the audible alarms and key presses have
an assortment of sounds.  An unacceptable key press generates a razz
type buzz, sort of like a Bronx cheer.  The arrival alarm is a
distinctive four note signal.  Whenever an alarm message is displayed
the GM-100 briefly illuminates its LCD backlight.  The assumption is
that the illumination will be off by default to conserve battery power, but
you will want to see the alarm message.

Menus are logically nested and easy to navigate with some special menus
for specific screens (windows).

Though I haven't seen a technical specification, Lowrance states that
the unit is waterproof.

It ships with a data cable with DB-9 serial port connector to mate with
a PC or DGPS receiver.  The cable also has unterminated power leads.
Also supplied is a cigarette lighter power cord for mobile use.  But if
you need data I/O while operating under automotive power, you will have
to attach your own lighter plug to the data cable pigtail or buy an
accessory data cable with lighter plug already attached.

              Now for the meat and potatoes!

The receiver is very sensitive.  In comparison to my ML-150, also a 12
channel receiver, the GM-100 is far superior in locking to weak and
fluttering signals.  When the ML-150 would only capture 3 birds, the
GM-100 would lock to 4-5 birds and show signal bars for 8.  I should
point out that my test range is the edge of a forest on a hillside in a
valley.  There isn't a lot of clear sky.

There is an abandoned camp/shed on my land under dense forest canopy.
None of my hand held GPS receivers work well there.  Typically I have to
get a fix in a clearing and then walk to this location.  Even so, I'll
lose lock often.  Not anymore!  The GM-100 was able to lock to at least
5 birds after being first turned on at that site.  And it refused to
lose lock!

I checked out DGPS mode using a CSI MBX-II Coast Guard beacon receiver.
I discovered quite quickly that you have to turn on either the Magnavox
or Starlink mode to get the GM-100 to listen for DGPS messages. But
unlike older Lowrance GPS receivers or the ML-150 you can leave that
mode permanently selected.  The GM-100 will simply ignore the absence of
DGPS data and function as though it were left only in GPS mode.  Most
other GPS receivers will periodically nag you with alarms warning that
you are not in DGPS mode.  Instead the GM-100 will notify you once when
DGPS mode is acquired and once upon loss of DGPS mode.  The default
time-out is 30 seconds for aging of DGPS messages and switching out of
DGPS mode.

The DGPS status screen is the only other indication of whether you are
in DGPS mode.  This screen shows you a list of SV's and whether the DGPS
data for each is good or bad and the aging time in seconds for the last
DGPS sentence update received.  Additional data includes the reference
station id number, frequency, data rate, signal strength, etc.  Only the
id number and age are displayed when used with my CSI beacon receiver.

I miss not having small D's in the signal bar graphs of satellites with
DGPS corrections as shown by many of the newer GPS receivers.  Instead,
you can assume DGPS mode if the accuracy value on the satellite status
screen is a single digit.

Some beacon receivers can be manually controlled from the GPS receiver,
but apparently not mine.  It isn't necessary if your beacon receiver can
be run in automatic mode or be manually controlled from its own front
panel.

Instead of providing DOP's like the older but highly technical AccuNav
Sport, the GM-100 and ML-150 display an accuracy value in feet.  This
provides a more intuitive indicator for most mortals.  The MicroLogic
also stores this value with every recorded waypoint for future reference
while the Lowrance does not.  The ML-150 displays this accuracy value on
its main navigation position screens. So you always know how good a fix
the position coordinates represent.  Unfortunately, the GM-100 only
displays the accuracy value on its satellite status screen.

Worse yet, the values are vastly different between the GPS's!  The
MicroLogic appears to be more conservative, reporting values more likely
to represent actual accuracy at the time of measurement.  For example,
with very good satellite geometry and an over determined solution based
upon 5 or more satellites, the ML-150 will report accuracy in the range
of 120 feet.  When I provide DGPS corrections, it will report accuracy
in the 18-25 foot range.  The Lowrance starts off with values in the 50
foot range and goes to 3 feet with DGPS data!  Who is correct?

The Lowrance owners booklet does state that the estimation of accuracy
is always based upon SA being off!  Thus they go on to say that the
estimation should only be taken as reasonable when in DGPS mode.  Sounds
like Lowrance is jumping the gun on the discontinuance of SA while
MicroLogic hedges its displayed guess by throwing in an SA fudge
factor.

Both units have differing forms of pinning behavior.  The ML-150, if
locked to at least 5 birds will show zero ground speed when held
stationary, even though the position data and altitude will continue to
change.  But the GM-100's ground speed didn't hold zero even in DGPS
mode! But its positional data did hold still with pinning enabled. I
later found if you give the GM-100 a minute or two and SA is not at one
of its accelerated moments the velocity will pin to zero.  You can
adjust this threshold.

On the seat of a car, the GM-100 locked to at least three birds while
the ML-150 failed to lock to more than one.  On the dash, they both
locked, but the Lowrance held lock under the heavy tree canopy of my
dirt road while the MicroLogic did not.  This is a good test since
invariably GPS's lose lock halfway down this road and often do not
re-lock on time to detect arrival at my home waypoint.

I had to maintain a physical separation of at least one foot between the
GPS units because under weak signal conditions the ML-150 appeared to be
desensed by proximity to the GM-100.

Since I travel a parallel blacktop road before turning onto the dirt
road I actually head towards and then briefly away from my home waypoint
when homeward bound.  The ML-150 simply beeps its arrival alarm twice,
once on the blacktop and again when I actually approach my driveway.

The GM-100 surprised me.  It gave me an overshoot, passed the waypoint,
alarm and then an arrival alarm as I got home.  Very nice!

The status window, satellites, of the GM-100 displays near instantaneous
changes in signal strength and lock condition.  You can see satellites
lock and unlock very rapidly!  And the unit will go in and out of 3D
mode instantaneously too.  No delays in either direction!  And the bar
graphs dance as fast as "S" meters!

The Rockwell 12 channel engine in this receiver is apparently very fast.
So the receiver tends to initialize and lock quickly, and it is
lightning fast at re-locking from a brief outage.  It is this feature
alone which will make the biggest difference when trekking through the
woods!  Overall, the GM-100 is the best performing hand held GPS
receiver I've had the pleasure to use.

I did note that, when first acquiring navigational lock or after a major
satellite fade, the unit did not resume navigation lock for a
significant interval, maybe 10-30 seconds.  And it will not start up
with only a 2D lock.  It insists upon a 3D lock to kick things off after
which it will accept a 2D lock once rolling, so to speak.

Even so, it would appear that the GM-100 promises to be an outstanding
hand held general purpose GPS with customizable mapping/charting
capability.  But viewing detailed maps on a tiny monochrome display is
visually challenging.  On the other hand, lugging around a 12 inch TFT
display on the back of a laptop PC isn't conducive to hiking!

Keep in mind, that if your goal is to have the best mapping detail with
travel databases, you won't find it in a hand held, though the new
Garmin Street Pilot comes close to that goal for urban use.  Your best bet
is still a laptop PC with a CD-ROM mapping database and large SVGA
color display driven by a decent GPS receiver.

A lot of readers are interested in a comparison with the Garmin GPS-III.
Unfortunately it will have to wait for someone who owns both.  But I can
say that since the Garmin line has the greatest generic PC utility
software support, this might be a decision factor for some users.

       Supplemental information about the GlobalMap-100

I recently had the opportunity to take my GM-100 on a 609 mile car ride
through the Finger Lakes region of New York State.  Here are my
observations.

My travels took me from Brattleboro VT to Ithaca NY and back.  Before I
started out on the journey I used various Internet sources to map out
the locations of specific highway intersections and destinations and to
acquire their geographic coordinates.  Thus I was able to create a bunch
of waypoints beforehand.

Every waypoint was on target!  The GM-100 arrival alarm sounded as I
approached every one of them.  I probably should have increased the
proximity alarm above .1 mile as there were a couple of off ramps that
came up with only a few feet of advanced warning.  But the ability to
pre plan a trip and set arrival alarms that worked without ever being
there was neat.

The receiver was mounted on one of those universal foam padded vise jaw
style cell phone holder's with a long telescoping arm with suction cup
attached to my windshield.  Thus the GM-100 was suspended in mid-air
just over the lip of the dashboard and canted slightly back to permit
the built-in patch antenna to see some sky.  The "look angles" for the
antenna and the LCD display were not great.  It was a compromise
position slightly favoring the antenna.  When the accessory passive
external antenna becomes available this compromise will not be
necessary.

As anticipated, continuous tracking and navigating was extremely good.
In over 600 miles the receiver only lost lock about 4 times and only for
very brief moments (2-5 seconds at worst).  Indeed, on the trip out,
there was only one instance of loss of navigation lock.  A loss of maybe
only 15 seconds total in a 5 1/2 hour journey over land is
extraordinary.

The only anomaly occurred outbound after a lunch stopover in Bennington
VT.  After resuming the journey the GM-100 lost lock and refused to
relock even though the status screen showed five SV's fully acquired!
Restarting the receiver cleared the problem.  My guess is that bad data
was received due to fading or other brief interference and was not
detected as such.  This can sometimes happen even with reasonable error
detection codes.  The anomaly did not recur.  Indeed, we did not lose
lock on the rest of the outbound journey!

The GM-100 has a fairly detailed background map of the entire US
mainland major highways and rivers.  When you download an IMS map
segment, the display will use the higher detail when the magnification
range is appropriate.  Unfortunately I needed three IMS map segments to
cover this journey.  The receiver has memory for only two.  Thus I had
situations where the display had an IMS map segment next to a lower
detail background map segment. The way the GM-100 handles such a
boundary can be disconcerting.  Below 15 mile magnification range the
display will favor the IMS detailed map section even if your current
position cursor is in the background map section.  Thus the background
section will lose all detail!  Zoom out beyond 15 miles and you will
force the display to choose the background map instead and you regain
details around your cursor position and beyond.

The background map will drop all details when you zoom in below 3 miles.
The IMS map segments allow zooming down to .1 mile.

The partitioning of the US mainland into IMS maps appears to have been
done in a manner that attempted to fill each segment with all the data
it could hold.  Remember that this data was originally written to ROM
cartridges.  Thus the segments often traverse awkward political
boundaries not conforming to one State.

The solution has arrived! Lowrance has been shipping a new CD-ROM with
"MapCreate" software that will allow you to design your own map upload files
with whatever boundaries and details you wish as long as the file size does
not exceed the memory limit of the receiver's memory partitions.  (See last section
below for a review of the new "MapCreate" software.)

Mapping accuracy was good with only one significant database error
noted. Route 7 in Troy NY does cross the Hudson River to allow a direct
merge onto I-787 even though the IMS map says not.  While this is a
relatively new bridge it has been in service for over half a decade!

Since the details disappear on the background map database when zoomed
in below 3 miles, I kept one of the map screens at the 3 mile range.
The path lines tended to stay within the highway lines most of the
time.  There were only a rare few instances where SA plus poor satellite
Geometry allowed the path to wander slightly off the highway.

I suppose one could write intelligent code that would assume the
receiver was in a motor vehicle and that you could not stray off a road
unless you were at an intersection!  Indeed, the new Garmin Street Pilot
does it.

I-90, the NY State thruway, parallels the Erie canal from Albany to
Buffalo.  The canal was clearly visible on the GM-100 display.  Every
time the GPS indicated the canal was approaching the highway we could
see it too.  I enjoyed alerting my passengers to look for the canal just
before it appeared along side us!

On the return trip to Vermont I did lose lock a few times, very briefly.
The weather was overcast and rainy and I suspect that the satellite
geometry was less than optimal too.  The combination probably
contributed to the slightly reduced performance.  Even so, the fast
re-lock and ability of the receiver to keep navigation data flowing even
when it had only brief snippets from the satellites was outstanding!

Watching the altitude display, which for most purposes is almost
worthless due to SA, gives you an inkling as to how well the GM-100
performs.  GPS receivers, upon loss of 3D lock, will freeze the altitude
display at its last value and may blink until 3D lock is restored.  The
GM-100 will blink the display but the value keeps on changing, tracking
altitude and SA!  Apparently a fluttering signal is enough to keep the
altitude reading updated even when steady lock is not achieved!

              Additional Accessories For The GM-100

                    Passive External Antenna (EA-3)

The Lowrance external antenna comes with an 8 foot cable,
mounting bracket with a pair of small suction cups, a flat bracket for
permanent screw mounting to a flat surface and a plastic magnet sheet
which can be glued to the antenna to create a removable magnetic mount.

My antenna arrived with an instruction sheet claiming that the cable was
25 feet long.  It also mentioned a tube of epoxy provided for the magnet
installation.  However, no adhesive was provided.

The antenna is a passive design, no active amplification.  Instead, the area
of the patch antenna is large.  Thus it provides more gain than the smaller
internal antenna to make up for some of the cable loss.

Since the external antenna jack is not powered, there is no way for the
receiver to actively switch between its internal or an external antenna.
Instead it mixes the two signals.  This can result in some multipath.
But at the typical separation distance of a few feet, the induced errors
should be far less than SA and thus negligible.

I did find that, with the external antenna held about 1 foot (30cm) from
the GM-100, the signal strength of some of the satellites actually went up
a bit.  With the GM-100 mounted beyond the dashboard of my car and set
vertically for easy view, the addition of the external antenna attached
to the windshield provided somewhat higher signal bars, actually equal to the
internal antenna when the GPS was in a more ideal position for reception.

But caveat emptor!  The mixing of signals from both the built-in and external
antenna created worse performance than using the internal antenna alone!
Apparently the mixing resulted in enough random phase cancellation to cause
much rapid signal/data dropouts.  This slowed initial satellite acquisition
because it took the GPS longer to get the quick ephemeris data from each
satellite.  And it seemed as though the GPS had a greater tendency to lose
lock once under way.

I suppose one could wrap some aluminum foil around the top of the GM-100
to shield its internal antenna under that circumstance.  But that would be ugly
and messy!  And it might result in degraded SNR overall even with a good
signal from the external antenna.  So, about the only viable use for the
external patch antenna might be onboard an airliner in the passenger cabin.

Thus I cannot recommend the use of the Lowrance passive external antenna
with the GM-100 for any application wherein the GPS is not substantially
shielded from satellite reception.
 

                        MB-2 Mounting Bracket (RAM)

The Lowrance mounting system for the GM-100 and similarly packaged
units utilizes a custom cradle which has mounting screws that match
the standard AMPS cellular bracket hole pattern.  The top of the cradle is
split to permit flexing around the GM-100 case, thus providing a firm
but easy to release hold.  Accessory cables can be dropped through
this gap after they are conveniently connected to the rear of the receiver.

The double ball gimbaled mount is 4 3/4 inches long.  This is way to
short for most available mounting surfaces in an automobile, though it
may be fine shipboard.  The hardware is made by RAM.  And their
catalog shows all sorts of accessories such as goosnecks, extension
pipes, larger ball mounts, etc.  But they cannot provide the custom cradle
for the GM-100.  Lowrance will not sell the cradle by itself.  So
most practical mounting arrangements will require additional purchases.

I took the Radio Shack extendable suction mount  that I had been using
with its foam jaw type of universal cradle and attached the entire MB-2
assembly to it.  This provided a custom cradle with a dual ball joint gimbal
for more flexible positioning of the GPS. I have now positioned the
GM-100 so it is easily viewed while driving The LCD display is far more
readable when viewed head on away from the glare of the windshield.

           New "MapCreate" Software CD-ROM

It took me a while to be able to test out Lowrance's new "MapCreate"
software as it was written for execution only under Windows 95 or 98.
So, I've been busy installing Windows-98 over Windows 3.11.  That is
an adventure story for another day.

Lowrance has packed much more mapping detail into their "MapCreate"
database than is available on their IMS map cartridges or "MapSelect"
CD-ROM. The detail is stunning.  For example, the rural dirt road, down
which I live, is not only on the map, it is named too!

The tradeoff is the amount of additional memory required to display such
detail.  Thus the size of the mapped areas must be made smaller in order to
fit into the two one megabyte partitions in the GM-100's flash memory.

The new software gives you the option of turning off layers to reduce the
file size.  You can deselect railroads, streams, bodies of water, names, etc.
But since you can draw your own boundaries around data squares by
connecting the dots, you can create long thin maps that will cover not only
a specific place of interest but also your route to it.

For example, I created two map segments that cover my route through
Vermont to New York City. It includes parts of nearby New Jersey, all
of NYC and much of Long Island.

Just how useful is the MapCreate database in a major city?  Well, in an
urban environment many of the smaller streets are not included.  However
most large thoroughfares are.  In NYC, all of the major north/south avenues
are listed and named.  For example, Broadway, Bowery, 1st through
10th Avenue, etc.  In a gridded city that is much longer than its width, it is
sufficient information to get you around.  While it won't locate a specific
street address, it will let you know approximately where you are and which
way you are travelling.  It is very easy to get disoriented in the cavernous
streets of New York.  And being able to see your path is more than reassuring.

I recently drove into NYC, something I haven't done in over 22 years.  The
directions of well meaning city dwelling friends, who don't drive, were wrong.
The GM-100's map display showed that a certain avenue was not going to be
accessible from the street we were on.  The GPS was correct!  Indeed I was
able to navigate around the city without resorting to a detailed street map. The
combination of my dim memory of NYC's layout plus the GM-100 were
sufficient.

Lowrance is concentrating on rural locations for outdoor enthusiasts who
would be appropriate users of hand held GPS receivers.  So urban street
level detail is not its forte.  If you frequently pilot around a major city consider
either Garmin's Street Pilot or the addition of a laptop PC with mapping
software that can be driven by your GPS.  If you occasionally travel into the
big city, the GM-100 does provide enough major roadway detail to be of value.

(See the screen shots of the  new MapCreate CD-ROM system HERE.)
 

            Oddball Uses For Hand Held GPS Receivers

Recently, a niece came to visit.  We took her up to the Bromley Mountain
Ski Resort where in the summer they boast the longest Alpine Slide in
the east.  You take a chair lift up the mountain and then slide down a
very curvy track or chute on a small plastic sled with nylon runners.
My niece followed me down on our first run, complaining that I wasn't
going fast enough for her.  Great Scott, it seemed more than adequate
for me!  So on the second run, she went first and I followed behind with
the GM-100 in one hand.  According to the GPS receiver my average speed
was a paltry 10 MPH with bursts up to 14.7 MPH.  Whew!

--Ira