On The Water
reprinted from THE FISHERMAN
 By Capt. John N. Raguso

SI-TEX GPS-90/GPS-90D TRACK PLOTTER
As we enter the new millennium, SI-TEX engineers continue to take one of the leadership positions in the very competitive world of marine electronics with the introduction of their new GPS-90 and GPS-90D navigator/track-plotters.

A USER-FRIENDLY APPROACH
The problem with many entry level GPS navigator units is that their simplified keyboards and multi-menu driven operating command structure usually translate to an excessive number of operator keystrokes when initiating the laborious task of entering your favorite fishing holes and channel markers. Sure, some of the top high end chart-plotters costing many thousands of dollars afford a one-touch, point-and-click ability on a super-sized color LCD screen, but the majority of the GPS navigators under the thousand dollar benchmark typically employ the tedious multiple step waypoint input approach. The SI-TEX design team has done their best to make this ergonomic challenge ancient history with their new GPS-90 and GPS-90D track-plotters.

Both navigators feature a waterproof, full-function keypad engineered to minimize the number of user keystrokes required to enter positional data into the non-volatile internal memory, which can store up to 400 alpha-numeric waypoints, plus 20 reversible routes with up to 20 waypoints in each. Although both machines offer an advanced, continuous-tracking 11-satellite parallel receiver, the primary difference is that the GPS-90 is a basic navigator/track plotter, offering the user only 100-meter accuracy, due to the Department of Defense's Selective Availability policy that intentionally degrades the GPS satellite signal.  In contrast, the GPS-90D is equipped with a built-in differential beacon receiver that improves position accuracy to a tighter 3-to-5 meter circle, which is critical when searching for a small piece of "fishy" structure like a reef or wreck, or when attempting to find an inlet or tight channel in foggy or low light conditions.

THE RIGHT STUFF-
The SI-TEX engineers have done an excellent job downsizing the physical footprint of the GPS-90 unit, which measures less than nine inches wide, six inches high and four inches deep, complete with yoke mount.  If you opt to flush mount this unit (a special kit is available at extra cost), the dimensions are even more svelte, ensuring that just about every boating angler, from a 17-foot center console to a 50-foot-gold-plated sportfisherman, can find a useful spot on the helm's dash panel for a GPS-90.  The weatherproof, backlit liquid crystal display takes up most of the area on the unit's front panel, offering excellent visibility of all screen data, with the weatherproof keyboard organized neatly in a three-column array to the starboard side of the case.  Unlike past SI-TEX navigators (like the former GPS-9 and 9D) that took an elementary "numbers only" approach to display screen data, the new GPS-90 units offer numerous graphic screens that include a digital compass, plus an electronic fairway display that shows the vessel's rhumbline course, cross-track error and progress to the desired waypoint.  A "north-up" X-Y axis track-plotter is also part of the display mix, which can come in handy when looking to chart your boat's course when trolling offshore structure and visually analyzing where your best action has taken place in order to set up a repeat performance.  With up to 2,000 plotter tracks available for use, with track ranges that vary from 150-feet out to 20 nautical miles, you can accurately retrace your steps and any previous trips with pinpoint accuracy.  Other screen options include a dedicated man-overboard function, which stores the precise position and provides a graphic perspective with continuous updates of range and bearing, in addition to a comprehensive menu command display.  Both SI-TEX GPS-90 units allow you to transfer your favorite Loran-C TD fishing hotspots with a built-in automatic Lat/Long conversion that employs a mathematical algorithm to make the switch, which should put you in the general ballpark.  An NMEA 0183 data port allows seamless connectivity with compatible charting systems, radar, autopilots and depth sounders.

Both the GPS-90 and the GPS-90D are street-priced under $1,000 and carry a two-year limited warranty.  For more information, call SI-TEX at 727-576-5734 or visit them on the internet at www.si-tex.com

SPECIFICATIONS
Dimensions – 8.7 inches W x 5.2-inches H x 3.6-inches D
Receiver type – Parallel GPS, 11 channels
Position data display – Lat/Long, Loran-C, Loran-A, Decca
Waypoint Memory – 400 alpha/numeric waypoints
Route Memory – 20 routes with up to 20 waypoints in each
Display type – 128 x 64 pixels, backlit waterproof LCD