WHAT DOES A GPS RECEIVER DO?
A GPS receiver is a RECEIVER of radio signals and it does not transmit anything to anywhere.  The GPSR provides as its primary function,  the ability to locate your CURRENT POSITION anywhere on the planet. Normally, it can do this to an accuracy of perhaps 6 to 8 meters with 95% certainty depending on obstructions to the sky.  Some models also have built in (or uploadable) maps to allow you to view on the GPSr's screen your current position.  Also selected models will receive WAAS corrections, resulting in accuracies of 3 to 4m 95% of the time as shown (HERE), PROVIDED your are in the clear. WAAS is more susceptible to tree cover than non-WAAS.

PLEASE NOTE:
For a GPS to lock on, it must receive a COMPLETE navigation message that takes 30 seconds to transmit from each satellite.  If you are moving, the slightest blockage from a tree limb or reflection from a building will prevent perfect reception, so the 30 second cycle is repeated -over and over.  The best thing to do is hold the unit perfectly still so that the signals to the unit don't "flicker" and ruin the reception.  Once locked on and under way, there is so much signal redundancy, the unit will remain locked even with partial signal reception. So, get lock first, and travel later!

MAPS:
Generally, the current state of the art in mapmaking is such that most times your position on the map will be pretty accurate, but in some places, errors of tens or hundreds of feet will be found in the maps.  Some maps (such as world maps or built in "base" maps have larger errors).  Maps are being improved constantly, but the world is a big place and the number of mapmakers working on improving consumer maps is small.

Some (mostly mapping type) GPSRs have the ability to FIND locations such as: POIs (Points of interest) such as restaurants,  hospitals,  malls,  markets,  police facilities,  hotels,  garages, banks,  and other such places, single street addresses,  road intersections,  cities,  waypoint locations and similar.  This capability varies widely and you must research what you want BEFORE you buy a unit.  These mapping equipped  GPSRs are NOT normally equipped with data to FIND the more obscure points of interest such as cemeteries,  swimming pools, and a host of other such.  However, if you already KNOW the longitude/latitude of, say, a cemetery, then the GPS can point you right to it.

GPS receivers and map software are continually getting more features.  The following is a description of the most popular hardware and software currently available.  Since individual products don't contain all the features available, hopefully this review will allow you to be a more informed buyer and put together the combination of products necessary to obtain the features YOU need..

The first handheld mapping GPS from Garmin was the G-III+ ($350 v. 2.04) released in Jan. 1999.  (Map CDs run from $75 to $150).  Next came the G-12Map ($330 v. 2.04) in Oct. 1999, eMap ($250 v. 2.50) released in Nov. 1999,  and the eTrex released in July 2000. Then came the eTrex Summit, Legend/Vista, and later the GPSmap 76 in 2001.  The GPS-V Autorouting receiver arrived in October 2001. In 2002 we have the GPSmap 76S (sensors).

Mapping GPSs include a base map of all the Interstate, most of the state routes, railroads, rivers, and shorelines in the Western Hemisphere with seven levels of detail.  An International version contains road maps of most countries in the rest of the world, and the Atlantic versions have higher-detailed maps of Europe.  The eTrex Summit is the only non mapping GPS we have reviewed lately, but it contains features new to hand-held GPS receivers.

Basic features of the hand-held Garmin mapping units are:
At least 500 waypoints storage, 20 routes of 30 or 50 routepoints, and 2,000 to 5,000 trackpoints.  All have a Track Back feature that converts a track to 30 to 50 routepoints providing steering directions to navigate the Track Back route -either way.  All current units have icon symbols for waypoints.  Erasure of Track Back waypoints is now easier with "delete by symbol".  All have a serial data or external power capability.  A "three-way" cable provides for both.

The receiver performance in the Garmin GPS receivers is good enough in many cases, so that  an external antenna will not be necessary.  Reports indicate that you may need an external active antenna to maintain continuous coverage under difficult terrain and tree cover conditions.  Garmin makes three active antennas, the GA-26(C) and GA-28 (29) for the G-II/G-III(+) series receivers BNC connector and the GA-27(C)for the MCX connectors of the G-12XL, eMap, and GPSmap 76.  "C" designates a low-voltage version. The GA-28 (or low-voltage GA-29) pole mounted 'marine' antenna comes with a 30' cable.   An MCX to BNC adapter cable is available if necessary.  Garmin receivers are also compatible with most 3rd party amplified GPS antennas as well as Garmin brand.  Tri-M is the only other antenna vendor making an amplified external antenna compatible with Garmin's MCX antenna connector.

Some general differences are:
The G-12 and G-12XL have internal antennas.  The G-II+, G-III(+), and StreetPilot (ColorMap and III) have rotateable external antennas with a BNC connector.  The G-12XL, G II+, G-III(+), GPSmap 76, and StreetPilot (ColorMap) have powered jacks for remote antennas, but the G-12 and eTrex series have no external antenna capability. The eTrex Legend and GPSmap 76 have fixed 8MB of map memory, where the Vista has 24MB fixed.

Only the G-12XL, G-12Map, eMap, GPSmap 76, and GPS-V have an audible alarm.  Only the G-II+, G-III(+), and G-V have rotateable screens (Horiz. or Vert).  The G-II+, G-III(+), G-12, G-12Map, and G-12XL, units run about 20 hours on (4) AA alkaline cells.  All Garmins will accept external 12vdc power and serial data through a four pin plug, except the G-12, G-38, G-40, eTrex (Series), and eMap which require a voltage regulator.

The G-12Map, eMap, eTrex (all), and GPSmap 76 units operate at 3.0vdc and require "low voltage" antennas such as the GA-27C or GA-26C.  However, these low-voltage antennas will also operate on the older "high-voltage" receivers.  The "26" antennas have a BNC connector while the "27" antennas have an MCX connector.  Check your receiver to see what kind of jack it has!!!

Garmin Hand-held Receivers:

GPSmap 76S: Ver. 1.06 is about $375US.  The 76S is physically the same as the 76, has the same screen resolution (but has 24MB of map memory instead of 8MB for the 76).  Also the tracklog has been increased to 5000 trackpoints, and the case colors are reverse  The unit has an internal barometer that is considerably different from the Vista barometer.  For one, the Vista calls the local weather bureau barometer setting "Normalized" pressure where the 76S calls it the "Barometer" pressure.  In the Vista, the Normalized pressure readout would change inversely, if you were traveling up and down.  (The barometer reading should not change when moving up and down except as atmospheric pressure changes).

The 76S also contains an electronic compass.  This appears to be the same compass as in the Vista, except it has a larger display.  It is activated when the unit is traveling slower than some selectable speed.  When calibrated on a non-metallic flat surface in a magnetically undisturbed area, the 76S heading accuracy was within the spec limit of 2°.  Although no warning is displayed when batteries are replaced (as with the Vista) the unit should be re-calibrated in order to retain its 2° accuracy.  By holding down the Page key, one can quickly turn the compass ON and OFF as needed. The barometer and GPS altitude are constantly combined with a filter to provide the best measure of altitude.

GPSmap 76: ($310 v.2.04) is quite a lot of GPS for the money.  What does it have going for it?  A larger, higher-resolution screen than the eTrex series, (WAAS),  map or marine navaid capable, many customizable options, all buttons on the front for easy access, and features not found on other Garmin units. The unit superficially looks like an eMap with the same screen size and key layout  above the screen with a layout similar to the G-III+.  The screen is 180x240 pixels as compared to the eMap's 120x160 and the G-III+'s 100x160.

The unit is somewhat bulkier, weighing (with NiMH batteries) 228g  as compared to the eMap's 196g, but  lighter than the G-III+ 251g.   However, the GPS does fit in a shirt pocket.  The unit is surprisingly light for how large it is; this allows the unit to float.  The GPSmap 76 has 8MB of memory, and if you are a G-III+ or G-12Map user, this is a good upgrade.   You can load all of Garmin's map types, although only one MetroGuide area, so there you may be a little cramped.  The unit does support the address look up and next-intersection features like the eMap.

eMap: ($250 v. 2.50) is a NEW KIND of GPS receiver system.   It's basically a "shirt pocket size" GPS with simplified controls and features, far fewer than in "ordinary" GPS receivers designed for hiking, boating, or aviation. Instead, eMap is designed to be an Electronic Map  with a mid-size high resolution viewing screen. eMap can load (at the same time) any of the MapSource MetroGuide, WorldMap, USA Topo, and Roads and Recreation CD maps into its 8 or 16 megabyte optional memory.   Note:  MetroGuide maps are the most complete and most accurate electronic road maps for the USA that we have seen.  For comparison of the different features in MapSource and MetroGuide maps go (HERE).

When using MetroGuide maps, the eMap provides "RoadLock" whereby, if you are within a few feet of a road and are traveling at least 23mph, your current-position icon will "lock to the road" thus eliminating GPS errors. (When used with any other MapSource map,  roadlock does not operate.)  A major feature of v. 2.50 is that with roadlock, it will display each side road coming up in time to make a turn.  This is helpful when looking for side streets in the DARK!  With a MetroGuide map, you can FIND any of the following map features: waypoints, cities, freeway exits, Points of Interest, Street Addresses, and point to it on the map.

GPS-III+: ($355 v. 2.05)  represents the first step by Garmin to provide street-level detail in user-uploadable maps.  User map memory has a built-in 1.4MB of flash RAM, programmable from MapSource CD ROMs.  If the total map size is within 1.4MB, they can be uploaded at 115,000 baud (max speed).

The G-III+ has new features that permit you to locate the nearest  cities and expressway exits.  This feature only recognizes Interstate Highway exits with the "nearest exit feature".   Airports and some service facilities are also marked on the  new base maps. The base map is said to be more detailed than that of the G-III.  Garmin issued a WorldMap CD in Feb. 1999.

eTrex Summit: ($210 v. 2.05) is an upgraded eTrex package with the addition of a built-in electronic compass which shows your receiver heading even when you are not moving, and an altitude profiling system showing a profile of your elevation movement along your route of travel.  These new features are made possible by a built-in electronic flux-gate compass, and barometric altimeter.  The compass is compensated by the user turning around slowly twice in an interference free area.

The compass display changes from direction-traveled to direction-pointed depending on a user selectable minimum speed and time.  Readouts include maximum and average Ascent and Descent distances and rates.  The altitude profile can also indicate pressure changes over time.  The Summit has the highest resolution tracklogs while walking of any Garmin receiver.  See plots (HERE).

eTrex Legend: ($225) and Vista: ($300) are Garmin's latest in the low cost eTrex line.  These models offer a mapping memory capability for the MapSource MetroGuide maps.  The Legend has 8MB of memory, and the Vista 24MB.  The Legend/Vista are the first of Garmin's new product line to offer built in (WAAS) which improves position measurement accuracy.  The Vista and Venture models offer more and less functionality then the mid range Legend.  Selected screen shots are shown (HERE)

The Venture, Legend, and Vista are upgraded eTrex packages with the addition a "rocker" switch to the upper left of the screen along with  the position augmentation of WAAS.  The new high resolution display is 160 x 288 pixels and is easy to read. While the Magellan Map-330 now has the capability for WAAS,  Legend/Vista are the first consumer model GPS receivers to actually offer this capability. The Legend model does not have the compass and aneroid barometer included in the VISTA model which is otherwise similar.

Garmin Mobile-Navigation Receivers:

StreetPilot 2610 Touchscreen: This is Garmin's latest generation of GPS receivers with street level mapping and automatic route navigation for your car.  It is their first model with Finger TOUCH SCREEN for data input and control -and- map storage up to 2GByte Compact Flash memory cards  -and- USB data interface for map loading and data input/output.  The 2GByte CF card will hold the entire CityNavigator 5 maps (1.44Gbytes) for the USA (including Alaska/Hawaii) and the maps of covered Canada areas.  This sleek unit has the GPS antenna integral within the unit and  is designed to fit on top of your dash and provide visual and audio directions for navigating your car on unfamiliar streets and roads.  A  battery powered IR remote control is provided so that passengers can program the unit even from the back seat.   ALL functions of the SP 2610 are operable from both the main unit and the remote.

We think the StreetPilot 2610 has the best USER INTERFACE we have seen in a car navigator. There are four push buttons for major functions (PAGE/mark, MENU/route, FIND/recent, and SPEAK/volume. (The first function requires a momentary button press, the second requires that you hold the button in for about 2 seconds.) New to SP 2610 is that it is designed without internal batteries and operates ONLY when plugged into an external 10 to 24vdc  power source.  Uniquely (to Garmin equipment), the SP 2610 automatically turns ON and OFF with the power application from its external power cord. A switch is provided to turn the unit on and off manually as desired.  SP 2610 was designed from the ground up to economically replace  the   combination of GPS/Laptop Computer/Mapping Software system that many use to maneuver around cities in the USA.

StreetPilot-III: Garmin's StreetPilot III is their first model with automatic present-position-to-address routing and voice command.  This unit comes with a copy of Garmin's City Navigator mapping program which (using NavTech maps) has the most detailed highway and residential street level electronic maps available for the USA today.  Currently, the USA coverage area for City Navigator is (approximately) 120 largest metropolitan areas.  Outside these metro areas, enhanced "base maps" cover the entire USA with a map of major highways and interstate freeways. One region of 10 different pre-defined regions in the USA and Canada is provided without charge.  Other region unlock codes can be purchased (HERE).

The SP-III allows a user to automatically route using both the CityNavigator, MetroGuide USA, or the Base Map.  Thus, with a "routable base map",  you can automatically route from an address in New York City to San Francisco with only CityNavigator map sections for NYC and SFO loaded.  The SP-III is the only autorouting system that we are aware of that can do this sort of intercity routing without the need to load intermediate maps as you go from one region to another.  SP-III is the lowest priced Automatic Car Navigator (with voice) and one of the best performers.

GPS-V: ($415) is a versatile navigator that delivers automatic routing, detailed mapping and (WAAS) capability —all in a compact handheld GPS.  It comes with the MapSource City Select CD from NavTech, which gives you access to detailed street-level maps with locations of restaurants, hotels and other services.

Use the GPS-V to look up a location and it will automatically calculate a route and guide you to your destination with turn-by-turn directions and audible beeps that alert you to upcoming turns. You can switch the display from horizontal, for mounting on a bike or a vehicle dash, to vertical for handheld use.  The G-V is visually identical and functionally similar to the G-III+ but with autorouting, WAAS, and some other features.

The GPS-V (and StreetPilot series; StreetPilot, StreetPilot ColorMap, and StreetPilot-III with the flash memory cartridges), can upload any of Garmin's MapSource maps on CD.  The SP receivers at first sight looks like an "inflated" G-III+.  However, in their ample interiors are some significant hardware and software innovations.  A summary of the major features of the GPS-V, SP, SP CM, and SP-III are:

• Point-to-point route generation with MapSource MetroGuide.
• Present-Position to destination point automatic route generation (in the GPS-V and SP-III.)
• 'Rubber-banding' route segments attach to the street curves.
• Route guidance with large arrow that anticipates turns and street bends.
• Switch to track-up displays when approaching a turn.
• Map changes zoom level when approaching route turn.
• List user attractions, motels, restaurants, etc. near current position.
• Automatic "Next Cross Street" display with MetroGuide maps.
• Automatic inverse video amber backlighting at sundown.
• Driving Status text at top of map describes present location and up-coming turns.
• Map finds selected street addresses.

The StreetPilot-III and the GPS-V  (and the maps that come with them) require no help from a PC to generate automatic routes (see above).

Garmin Marine and Chart-Plotter Receivers

GPSmap162: $360 ($400 with external antenna), was reviewed with Fishing Hot Spots maps (v. 1.27) loaded.  The unit is a 12-channel marine unit which will include (WAAS) when using S/W ver. 2.60 or higher (this can be downloaded at no charge from the Garmin Web Site).  It is programmed with an internal base map, Americas 2.0.  This map shows the land masses and some of the major cities around the world, and major highways and waterways in the U.S.  Garmin MapSource maps can be programmed into it for areas of the U.S., Canada, or the world. These maps make the GPSmap 162 a versatile navigation tool that can be tailored to any part of the world.

This unit will NOT accept the Garmin G-Charts, detailed navigation charts for off-shore or inland waterways.  The GPSmap 162 kit has an external amplified antenna that is about the size of a baseball with a 30 ft. cable that connects to the back of the unit.  It comes in a black case about 6 inches wide and about 4 ¾ inches high.  A cover is provided for the display when not in use. .

GPSmap 176: The GPSmap 176 ($571 list) is a 12 channel marine unit which includes (WAAS).  It is housed in an attractive black case about 5 3/4 inches wide by 3 1/2 inches high.  The G-176 comes in a color (G-176c, 16 colors) and a high contrast gray scale (G-176, monochrome) screen model.  We are reviewing the B&W (gray scale) model, as it has slightly better visibility in bright sunlight,  but the features of the two variants are otherwise identical.  The viewing screen is about 3 1/8 wide by 2 1/4 high (3 7/8 diagonal).

There is a mounting bracket included which increases the total width to about 6 1/2 inches. With three swivel joints on the mounting bracket, the GPSmap can be fixed to about any angled surface and still be adjusted for easy viewing.  Also available is an automotive mounting bracket for attaching it in a car.  The packaged unit comes with a PC data cable for programming from a computer serial port, and a power and data cable to use with external power and other data sources. The unit can accept a DC source of  8 to 35 volts for external power. Although listed as a marine unit, the GPSmap 176 is quite suitable for using in an automobile when programmed with the available highway maps.

Garmin Software Compatibility:

All Garmin hand-held receivers are compatible with all the map software programs we have tested that use the NMEA 0183 Ver. 2.0/2.3, 4800 baud standard for real-time tracking.  Later units and firmware revisions have Garmin's "PVT" protocol so that switching back and forth between NMEA and GARM/GARM modes is no longer necessary to change from position tracking to data upload/download when using a compatible external mapping or support software.

G7ToWin: Can download (the last listed) Route, Waypoints and Tracks retaining the 10-characters in the Waypoints and Routepoint names.  During this process G7ToWin can create .SA4/5/6/7/8/9 files that show the data on Delorme's Street Atlas (but not Street Atlas 2003).  G7ToWin can also upload these files back into the GPS with the 10-character names and original Symbols preserved.  Routes that rubber-banded before downloading will rubber-band again after uploading, and old 6-character archived waypoints can also be uploaded.  Another feature of this program is that it can download and display as .bmp files the screens of most all Garmin units.

See examples of WorldMap  maps (HERE) and USA Topo maps (HERE).  Some receivers require a flash memory cartridge for these maps.  They can be purchased as follows:  8MB ($60), 16MB ($90), 32MB ($120), 64MB ($195), and 128MB ($310).

Roads & Recreation CD maps ($75) are more 'readable' in that major streets are designated with darker lines and more street names are provided.  Water detail is now on a par with that of Lowrance's MapCreate.  Shoreline detail is slightly greater than MapCreate, but R&R Nautical Navigation Navaids markers are considerably fewer.   These maps are essentially Tiger maps also used by Street Atlas and Lowrance MapCreate (examples shown (HERE) indicate a later database than Lowrance's MapCreate).
However, the Magellan Map 330 CityStreets map CD is of a later database than the R&R CD.

USA Topo set of three CDs ($100) is a later Garmin map product.  Topographic data is added to street-level maps.  These contain contour lines and extensive small stream data for the USA.  The road database is 20 to 30 years old, but are more accurate than those in the R&R CD or any version of Street Atlas.  They are: Alaska/Hawaii, USA West (Setup), and USA East.  Areas to be selected are now rectangles of various sizes in a grid.  Contour lines are those of the USGS 1:100,000 topo maps and are in multiples of 10 meters to 50 meters, depending on terrain steepness.  On the larger lakes, elevation contours (not depth contours) are also shown.

In addition, nautical navaids for the 50 states are provided, including radio beacons, RACONs, fog signals, river, harbor, and other lights, day beacons, and lighted and unlighted buoys. Wrecks and obstructions such as shipwrecks, submerged rocks, obstructions and other hazards to nautical navigation are displayed.

WorldMap CD maps contain many Nautical Navaids around the US coast and the rest of the world.  The street/highway detail and accuracy, however, are relatively poor.  Several Garmin and Magellan WorldMap examples are shown (HERE)

The most noticeable characteristic is that the screen is exceptionally clear and bright with (16) colors -especially with the backlight ON (which also backlights the keys).  The default ON is with the screen backlighted to maximum.  Pressing (and holding) the power button decreases the backlight to half and then to OFF.  The backlight can be set to turn off from 30 seconds to ten minutes.  Any time a key is pressed, the light comes on for the selected time and brightness.  This procedure enables the screens to be read easily in any lighting condition.  The Color screen is much more visible than the Magellan ColorMap and has about 50% more (Pixels) than the Pro.

Compass:
The 3-axis compass is a major plus for Magellan over Garmin.  The compass retains its accuracy with any tilt angle.  With the Garmin GPSmap 76S, you have to hold the unit vertically for best reception but horizontally to read the compass.  The map and compass can be oriented to Magnetic or True North, and the compass will read out in Degrees or Mils.  To switch off the compass (for use in an automobile, for example), use MENU, Setup, Compass Orient, GPS Course.  The compass will then show direction of travel.  Garmin units accomplish this with just a push of a button.

Magellan SporTrak Pro: about $250US, appears to be a Magellan Map-330  packaged in a more ergonomically pleasing package, and is 14g lighter.  Named keys are replaced by symbols.  The screen resolution is the same, but the Pro screen is a little whiter, more visible, and the backlight is brighter.  The keys are smaller and not quite as easy to use.  The Pro has the same operating system as the Map 330 with the addition of a 3-D "Road Screen" which is the same as in the Meridian Gold.

The Pro comes standard with a base map consisting of cities, highways & major roads, waterways, airports, parks, fixed navaids, buoys, lighthouses, marinas, and obstructions.  The SporTrak Pro basemap is the same as the MAP 330M base map.  The SporTrak Map comes standard with a base map consisting of cities, highways, airports,  The 330 contains Cities, Highways, Airports, Waterways, and Parks.  The Pro has these and adds Fixed Navaids, Buoys, Lighthouses, Marinas, and Obstructions, waterways, and parks.  The SporTrak Map base map is the same as the Meridian GPS base map.

The Pro memory includes 9MB of base map and 23MB for uploadable maps.  This compares to the 330's 8MB of base map and 8MB of uploadable map memory.  The SporTrak Map has a 2MB base map and 4MB for uploadable maps.

Magellan Meridian Gold and Platinum:
The Magellan GOLD (Ver. 2.09) Mapping GPS receiver (about $300US) is a full-featured and medium cost receiver with a built-in 16 MB basemap (competitive units have 8 MB, Meridian basic has 2 MB) showing worldwide political boundaries,  U.S. cities, highways, major roads, national parks, waterways and railways. The GOLD also has a slot for another 8 to 128 megabytes of flash "SD" memory available for uploading detailed street maps, waypoints and routes from Magellan's new MapSend Streets CD-ROM (sold separately).  Optional SD memory up to 64MB from vendors other than Magellan will operate in the Meridian units.  This receiver is larger and has a larger screen than the SporTrak Pro, see (HERE).  The GOLD has a feature lacking in most other GPS receivers; waypoints,  tracks, POIs, and topo lines can individually or globally be turned on and off.

A FIND waypoints, addresses, cities, highways, parks, waterways feature is provided.  You can even ask for the FIND to work "nearest the cursor" instead of nearest present position.  There are 8 sequential user screens.  You may turn any you do not want to use to OFF so the sequencing will take less time.  Fixed elevation (2D) or GPS elevation (3D) modes can be selected.  The GOLD can be programmed to automatically turn itself OFF if signals are lost for a user selectable period.

WAAS Compatibility:
The Meridian GOLD and family is WAAS and EGNOS compatible.  In addition,  Magellan has elected to
ignore the present "do not use" flag produced by EGNOS signals (the WAAS for Europe) and allow
corrections to operate in Europe.  Users should be aware that these signals MAY not  be reliable at
times.

When it come to trackback, Magellan has a significant advantage over the Garmin implementation.
The Garmins select only a few percent of the trackpoints to use in the trackback directions,  thus
tending to "cut corners".  This (from personal experience) can cause one to run aground when
following a curvy river in low visibility.  In the Magellan implementation, each and every trackpoint is
used in the trackback steering directions.

Meridian Platinum Compass and Barometer:
The function of this electronic fluxgate compass is an advance over the design of the Garmin compass.  Where the Garmin compass must be held horizontal to read, the Magellan three-axis compass can be read from horizontal to a tilt to vertical at which point the back of the unit is the heading being read.  The vertical position is also the most optimum position for signal reception, thus the best arrangement for locating a Geocache -for example.

COG (Course Over Ground) Pointer and Icon:
This unique pointer, not available in the Garmin units, is a useful new feature.  When using the Compass Screen to steer to a destination, the goal is to align the  destination Pointer and the COG Pointer together.  When both of these pointers are lined up, regardless of your heading, you are moving in a straight line to your destination.  This is a welcome feature for sailing enthusiasts.

Barometer:
In addition to the electronic compass, the Meridian Platinum provides a “mini-weather station” with
temperature and barometer information. The accuracy of the barometer is hard to discern.  Tests made in cool weather show that the barometer readings vary considerably with temperature changes.  As compared to our measurements of Garmin's 76S barometer accuracy of 0.02" Hg, the Platinum barometer appears not to indicate a useful measurement.
 

Magellan Map-330: (v. 2.03) $250US Mapping GPS receiver is an important evolutionary step in
consumer GPS receivers incorporating maps.  It is a full featured and low cost receiver with a built-in
8 megabyte basemap showing worldwide political boundaries, U.S. cities, highways, major roads,
national parks, waterways and railways. The M-330 also has another 8 megabytes of "flash" memory available for uploading detailed street maps, waypoints and routes from Magellan's new MapSend Streets CD-ROM (sold separately).   It's a direct competitor to the Garmin eMap.

Despite the relatively low cost and conventional design,  the Map-330 in our opinion is a step forward in mapping GPS products.  The unit can be updated to receive WAAS correction signals with v. 2.03.  And with MapSend Topo maps, the unit will display topographic and terrain-profile information in the direction of travel. While Garmin has used "product differentiation" by equipping low-cost models with small but irritating feature deficiencies while NOT offering a "full featured model with large map memory",  Magellan apparently decided to offer customers an attractive alternative.

Magellan 315:  The first thing you notice about the M-315 is its small size and light weight.  Where the ColorTrak weighs a hefty 13oz, the 315 weighs only 6.5 oz.  The comparable Garmin G-12 weighs 8.7 oz.  The unit only requires two AA batteries as compared to four for the Garmin.  The two units are approximately the same size, however the M-315 has a higher resolution screen.  See Dale DePriest's comparison table of these two GPS receivers (HERE).

The firmware version No. of the unit reviewed is 1.03 (which is visible at power-up).  Unit cost is about $150US and $39US for the data/power cable. Accuracy is stated as 15m rms exclusive of SA.  Upon detecting no receiver movement, the receiver automatically goes into an averaging mode in order to refine its position more accurately.  The M315 GPS has a  "The best time for hunting and fishing" feature.   There now is a simultaneous pan and zoom feature available in the M-315 latest software.

MapSend Streets and Destinations:
This map allows map transfer at 115,200 baud, and four disconnected regions can be uploaded.

MapSend Topo USA:
This map only allows map transfer at 19,200 baud, and the limit is also four regions.  The map contains both topographic information and what looks to be the MapSend Streets USA street detail.

MapSend WorldWide Basemap (with topo information):
Only one region of this map can be uploaded at a time.  It is possible to upload both street information (e.g. as in MapSend Streets USA) and the WorldWide Basemap.  The maps are not displayed simultaneously, but if you zoom out far enough, the WorldWide Basemap switches from the detailed map (if loaded) to the new WorldWide Basemap (if loaded).  The built-in Basemap can also be displayed if the WorldWide map is disabled.  The map-screen 'Scale' is 1/4th the width.  All of the many map details can be turned ON or OFF.

Automatic Map Switching:
The unit switches off the street detail from 350m to 700m  zoom and then switches to the WorldWide basemap map at 1.4km zoom.  At 2.5km, panning the cursor will reveal the closest waypoint to the cursor whether the waypoints are displayed or not -up to some unknown distance from the waypoints.  Past this distance, the cursor reveals the elevation.

Map Detail settings have no effect on the topo map except at 'Highest' where the street map always takes over at 2.5km zoom.  From the smallest to the largest region upload, the file was always about 1MB in size.  Apparently the first 800K or so is the program to generate contour lines from the Digital Elevation Model (DEM) database.

Map Utilities:
Map Utilities (also present in the Pro 4.04, but not the Platinum) is accessed from the first MENU selection.
It has two selections:
Change Map and Delete File.
    Change Map has selections of: BaseMap and Detail Map
        Under BaseMap: Default Map or BaseMap.mgn can be selected
        Under Detail Map: Detail Map Off or Secndmap.dat can be selected
    Under Delete File: Basemap.mgn or Secondmap.dat can be deleted
Normal operation would be with: Basemap/Basemap and DetailMap/Second-Map
NOTE: One must remember to "Save" these settings, before they will take effect.

There are four iFinder configurations,  each including the same GPS receiver but different accessories.  a) iFinder (basic) just has the GPS receiver and manual and nothing else.  b) iFinder Plus includes iFinder/Manual/MapCreate 6 and a 16MB MMC card and card reader, c) iFinder Atlantis is a marine model and includes a 16 Meg MMC card with high detail mapping of the continental USA coastline and d) iFinder Express is designed for inland USA use and has a 32MB MMC card loaded with much of the SEARCH ABLE POI database.

Lowrance Eagle Explorer: "EE" ($150) and GN 200 ($245) GPS receivers:  This EE review applies ONLY to those with firmware revision 1.4 or later (1.8 is current).  This firmware revision has substantial improvements over prior versions particularly in the area of working with moving map software packages.  The EE is a parallel 12 channel receiver which acquires lock faster and is more reliable at tracking in difficult conditions as compared with single and dual channel scanning receivers. The EE does not have an external antenna connector.  The receiver sensitivity on the EE (and the G 12) is so good that most will not require an external antenna.

The EE operates for about 6.5 hours on 4 AA alkaline cells and can also be operated on an external power source of 9 to 16 volts.  A useful feature of the EE is that it can accept a rechargeable NiMH battery which can be automatically recharged when the unit is connected to external power.  The receiver provides NMEA 0183 protocol versions 1.5 and 2.0 which (in firmware version 1. 4) is able to work with most moving map software.  (Note: The EE's simulator mode works only with Precision Mapping 3 and Ozi Explorer map software which ignore the 'invalid' flag.)

Global Map 100: v. 1.1 (Thanks to Ira Wilner) $200, (plus about $150 for the CityStreets map CD, data cable, and cigarette-lighter power cable), is the size and basic function of the Eagle series receivers which won't be repeated here.  GM100 was the first consumer GPS which allowed maps stored on CD-ROM to be uploaded into the receiver by the USER.  All the IMS Smartmaps originally available on single cartridges are now available on  CD-ROM.  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. The mapping data seems to be waterway heavy.

Lowrance has announced an upgraded CD-ROM package with much more rural road detail and the ability to create custom map files for upload.  (See the screen shots of the  new MapCreate CD ROM system (HERE). In order to display the new map data, the screen resolution has been increased to 104x160.  Unlike the Eagles, an un-powered MCX antenna jack is provided for a remote antenna, and the distance-to-go box reads in miles and then switches to feet as you approach your target waypoint.  Now most screens can be customized.

G7ToWinis a (free) Windows/NT program by Ron Henderson.  The program will download in one operation from the Garmin receivers, waypoints, routes, proximity points, tracks, and symbols (if they exist) to text and Street Atlas 3/4/5/6/7/8 files in all the various ways Street Atlas can present these data.

G7ToWin has been updated to support both Garmin and Magellan receivers with all the symbols Garmin has of this date.  It now supports the Street Pilot's 10-character waypoint and routepoint names for down/uploading and display and will interface with the new Street Atlas 7/8/9.  Upgrades will be available at G7ToWin above.  You have complete control as to how any downloaded track or route LOOKS in Street Atlas.  It can be solid, or 'highlighter', and be any SA color or thickness.  Routepoints can have Route No., names, comments, or none, and they are connected by lines, where with StreetAtlas they are not.  Waypoints can have names with or without comments.  StreetAtlas tracks are lines instead of dots.

EasyGPS  (free) is  an easy way to create, edit, and transfer waypoints and routes between your computer and many models of Garmin, Magellan, and Lowrance GPS units. Using EasyGPS,  you can manage all of your waypoints and routes, and display them in lists sorted by name, elevation, or distance.   EasyGPS connects your GPS to some mapping and information sites on the Internet, giving you easy access to street and topo maps, aerial photos, weather forecasts, and nearby attractions.    EasyGPS can exchange GPS data with EasyGPS, PanTerra and ExpertGPS users.

GPS Utility ($40) is an easy-to-use application that provides management and manipulation of GPS information. You can use it to transfer data to/from a GPS receiver and store the data in PC files in one of several text formats. The program converts between different map datums and many coordinate formats (Lat/Long, UTM/UPS, country grids etc.).  Information can be filtered in various ways and waypoints sorted according to specified criteria.

Using a scanned in bitmap you can digitize waypoints, routes and tracks. Route and track statistics are available and can be transferred into other programs for analysis (i.e. spreadsheet programs). You can plot your GPS information as a map and add map annotations in text or image form  GPS Utility is particularly useful for editing and splicing together track and route segments.  You can use it to convert tracks into a route and set of waypoints or convert Routes into tracks. Search patterns can be generated in either track or route/waypoint forms. Other tools allow you to analyze and average the GPS information. Routes may be exported as Route cards. Some special purpose file import and export functions are also provided.

GARtrip from Shareit by Heinrich Pfeifer (v. 115, US $30) is a Windows program that presents Garmin waypoint, route, and track data on a "white map" suitable for analysis and printing, true to scale. The program supports the Garmin G-12 and G-III symbols.  One feature includes converting coordinates from/to: Longitude/latitude, UTM, German Grid, Swiss Grid, French Grid (Lambert), British Grid, Irish Grid, Swedish Grid and any number of user defined grids, all with the proper geodetic datum. The program shows and accepts great circle distances between waypoints.  Advanced route planning with speed and time is included.  GARtrip imports and exports Garmin PCX5, Gardown, Garlink, Waypoint+, and OziExplorer files suitable for editing and uploading into the GPS.

Garmin PCX5 program ($75).  This program has been discontinued by Garmin in favor of  MapSource.  At last check,  Garmin was giving a US$80 discount to any current PCX5 owner toward the purchase of any MapSource or MetroGuide product.

Waypoints with NAMES and stored tracks can be downloaded and displayed on SA.  However, routes downloaded to SA do not show any lines connecting the routepoints.   An example of how G7ToWin
can distinguish between a mixture of downloaded waypoints and  routepoints (with lines drawn between routepoints) is shown (HERE).  Draw Object "Text Notes" and "Place Notes" (waypoints created by SA) containing Lat/Long  with the first 6 note characters are shown in the Names list; and the first 16 note characters are shown in Comments when uploaded to the Garmin receivers .  Uploading "Map Notes" results in no recognizable names or comments in the Garmin receivers.  Routes can also be uploaded  to Garmin and Lowrance receivers and to  later model Magellan receivers.  (Consult Delorme or Magellan for specific model compatibility.)

MapTech Terrain Navigator has a new presentation of a topographic maps in  3-D. The review compares it with Delorme's Topo USA 3.0.  Terrain Navigator can also show GPS waypoint, route, and track data on the 3-D maps.

Ozi Explorer v. 3.80 (Des Newman) $65US is similar to Fugawi with some added desirable features.  The first thing you notice is how fast it can import a CD of USGS DRG maps (30 seconds vs Fugawi's seven minutes).  The next thing is how easy and fast it is to pan the DRG maps (see example (HERE).  One click on the index map re-positions the main map instantly.  You can also re-position the map by "dragging" it.  Ozi allows you to leave your GPS on the Datum of the map, so that you can observe the Lat/Long in the same datum on both the GPS and the computer, the coordinates of  which will then be the same.  This approach requires that you remember to change the GPS datum when you change to maps with different datums.  Ozi is capable of displaying data stored on Garmin, Magellan and Lowrance receivers.

This version of Ozi recognizes BSB charts (see example HERE).  Unlike Fugawi, Ozi shows tracks and waypoints on the index map and can upload an individual waypoint by clicking on it.  Ozi supports Garmin Symbols up through the G-III+.  Ozi can register maps at nine points providing a better correction for distorted maps where Fugawi registers only three.  Both programs switch maps at the neat line. Up to 20 routes in different colors plus the Garmin Symbols can displayed by Ozi. (Fugawi displays one route and no symbols.)  Custom track logs can be created by Ozi but not Fugawi.  In the above version, Ozi can now print the maps to any desired pre-determined scale or coverage without loss of detail.  Fugawi also prints without loss of detail, but it's difficult to predict what will be printed.

OziExplorer also has a feature that will calculate an area of an enclosed GPS track or a manually-made track.  The results can be expressed in Sq. m, Sq. km, Hectares, Sq. Ft., Sq. Yds., Sq. Miles, or Acres.  Under Options is "Area Calculation".  When activated, one can load any stored track, and Ozi will calculate the part of the track that encloses an area.  An actual MAP is not necessary.  Just select the "Blank Map" and load the track.  As an alternative, one can CREATE an 'enclosed' track plot by clicking on selected area points of a loaded map which will also calculate an area.
See: Comparison Between Ozi Explorer and Fugawi.

Fugawi v. 2.19 (Sam Rea) is a $95 Windows scanned-map program which can upload/download, waypoints, routes, and tracks with the Garmin and current Eagle/Lowrance receivers.  Waypoint names are shown on the map next to easy to see small yellow squares with the names in black on green.  Placing the cursor over a waypoint causes its Description to be displayed.  A sky view of the satellites is included.

A double click on the map creates a waypoint which can be used as part of a route to be uploaded to GPS receivers.  The scanned maps will switch automatically as you travel along.  Routes are drawn with red lines, and tracks are blue linked cookie trail dots.  The GPS present position icon can be selected from several and will rotate as the direction of travel changes.  Fugawi allows the GPS to be continuously set to WGS-84 while the map datums are converted by the software.  This latest version allows control of printing any portion of the loaded map without any loss of detail.  Fugawi now has Canadian topographic maps available in the BSB format on CD.

NOTES:  One must remember to select Track/Record in addition to Track/Show in order to display the real time track.  With waypoints "Save on Exit" turned ON, all waypoints can't be cleared from the maps on re-load unless ONE waypoint remains.

Vista (v. 1.21) by RMS Technologies ($199):  This program can display and record real time GPS tracks on scanned raster maps, Vista Flight Sectional raster maps ($99 extra for each half of the USA), and Vista street vector maps.  It works with any NMEA 183 GPS output, including the Magellan.  The tracks recorded by Vista can be played back in seconds. Vista can show a vector map, a flight sectional, and a terrain profile at the same time! (Included with Vista is the geological elevation data for the whole USA to a resolution of 3,000' horizontal and 100' vertical.)  Thus the terrain profile between any two points in the USA or that in front of the direction of travel can be displayed in a small box.

Vista vector and raster maps can be installed on the hard drive one "square" degree of Lat/Long at a time to eliminate the need of a CD ROM.  Vista maps CANNOT be printed.  In order to display Garmin Waypoints, Routes, and Tracks on the Vista maps as Overlays, one must purchase the Garmin program PCX5 ($75) and obtain GARMIN.EXE (free) from the URL above.  (Note:  PCX5 has been discontinued.)

GPSS Moving Map by Robin Lovelock of Sunninghill Systems:  GPSS is now running in 115 countries, and you may download the software, and  over 1 GBytes of mapping for these countries from the web site. You may also download sound files to make it speak Japanese, Russian, Italian and other languages in addition to English. GPSS is issued free to the public as a means of contacting businesses around the world who supply it in large quantity, or use it for more specialized remote tracking applications such as radio,  cellphone,  OrbComm and Inmarsat-C satellite communications.

The free USA maps provide displays of the major highways and street-level detail in limited parts of the USA and Europe in response to e-mailed requests from GPS users as follows:  Support is provided for the street level mapping off the Microsoft Streets and Trips CDROM within USA, and AutoRoute Express 2000 CDROMs within Europe. The program supports a verbal command package for computer control as you drive along, but this is from another supplier at $50US.  Software support for the US Tiger data is available from the web site. The audio output tells you where you are about every two minutes.  This is really interesting for awhile, but annoying as time passes.  There is no way to adjust the announce interval, but you can turn the audio on your computer off.

The only production Garmin unit that can simulate moving from a keyed-in position is the G-12XL, which makes the unit useful for evaluating map software function and accuracy.  The Lowrance GM-100 can also simulate a keyed-in position and movement.  The Street Pilot (Color Map) cannot do point-to-point routing without outside help and is limited to 100 waypoints.  The Garmin eTrex series cannot do waypoint averaging.

The Garmin GPSmap series are very versatile receivers except, the green-cast screen is not as easy to read as others.  Generally, Garmin has more accurate maps available than the Magellans.

If you have any comments, additions/corrections, or to request a review of your PC mapping software or hardware, please let us know via Email below or by fax:
  Joe Mehaffey:   W2JO (770) 886-1767
  Jack Yeazel:    N4TEB (404) 255-5804

Thanks, and good navigating!

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