Furuno, who pioneered the use of Ethernet for on board data communication with the introduction of the NavNet Radar / Chart Plotter / Sonar control / display systems recently introduced a second generation of NavNet equipment, NavNet vx2. The changes from the first generation units are most evident in the radar / chart plotter multifunction units, both the black box versions and the integral display screen units such as the 1834C/NT.

At first glance the new 1834C/NT is almost undistinguishable from the predecessor 1833C. In fact, before you turn the power on the only visible change is the nomenclature on the chart cartridge door where vx2 is included in the NavNet logo. The unit is available for use with either Navionics Gold or C-MAP NT MAX cartography. Since I use a C-MAP equipped 1833C on my boat, I chose to evaluate the C-MAP version for this article. The improved processor in the new units allows Furuno to improve the quality of screen images, including the option of choosing the wallpaper that appears in the background of menu display pages.

The 1834C/NT can control and display radar, chart plotter, sonar, GPS navigation, and external video and weatherfax information. The data gathered from these sources can be mixed and matched in an almost endless variety of ways including numerous split-screen and overlay formats. The 1834C/NT's control system is carried over from the previous model and includes a trackball, a 10-button alpha/numeric keypad, a dozen dedicated function keys, and five multipurpose "soft" keys. The control system may appear complex at first but after performing the system set-up programming (best done with constant reference to the 190-plus page operator's manual); the logic of its design becomes obvious and will prove increasingly easy to use.

The 1834C can be used to control a wide range of Furuno radar scanners, from the 2.2 kW, 18-inch radome to the 72-mile range 1954C. Each of the main components of a NavNet system is assigned its own Ethernet address (an IP) making it easy to configure the system, including those with multiple displays and more than one radar scanner. The value of Ethernet for on-board data communication is attested to by its adoption by other marine electronic equipment manufacturers.

For most users the most striking change from the 1833C to the new, 1834C unit is in the chart image and the ability to extract a mass of supporting data from the chart database. The C-MAP NT MAX chart we used in the evaluation is packaged in a different format from that used in the previous Furuno CMAP plotters. An even smaller SD card that uses a 9-pad card edge connector replaces the small, FP, 50- pin connector plug-in card.

Although the previous card has worked well, the new card edge connector may provide some advantage from the superior wiping action of the socket contact fingers.

As before, the C-MAP cartography is vector based. Unlike raster scanned charts where a virtual image of a chart is stored in memory the vector chart consists of a mass of ?ĺnumbers?Ĺ that are used to recreate the chart image, while at the same time storing a large amount of supporting data in an easily accessed file format. The "depth" of chart data can be seen in the 24 item long list of chart attributes available for customizing the MAX chart presentation. Charts may contain photos of areas of particular navigational interest (designated by a camera icon) or detail information about marinas (shown with a sailboat icon) showing individual slip numbers. One of the viewing options provides a perspective view of the chart, essentially what you would see if flying over the area at an altitude of a few hundred feet. I think this option?Ĵs value may be greater when briefing a passenger about the planned voyage than for en route navigation.

Current flow is depicted on the MAX chart display with arrow symbols annotated with flow direction and speed information. Tide stations are designated as in previous versions of C-MAP charts with a "ĺT" icon, visible only at selected chart range settings. However the MAX charts provide an easy means to obtain a wealth of information, including tide data at virtually any point. Simply position the cursor at a location of interest and click the "enter" key. An object's dialog box appears on the screen providing a data list including references for port service, port list, tide stations, wrecks and obstructions. The port service list detail is accessed via a 51-item list of icons. In the event that a tide station reference is not available at the selected location clicking on the "find" menu will display a subordinate data list that includes reference to nearby tide stations, shown in order of increasing distance. A simple click on a station presents a complete tide record, accompanied with a set of astronomical data. The process is easier to do than to describe. The only tedious aspect of the implementation occurs when backing out of the data box, which requires successive key strokes. A single stroke "exit" key would be a welcome addition and would benefit many of the other control sequences.

Mariners who voyage in crowded waters and especially those who operate in and near major ports will be particularly interested in the optional 10 target automatic radar plotting aid (ARPA) and in the new interface module that when connected to an external automatic identification system (AIS) receiver can plot data from up to 100 AIS equipped vessels. The value of Furuno?Ĵs decision to use Ethernet for data communication will become obvious both when assembling a complex system and for mariners who are interested in using a Windows computer running MaxSea software as an adjunct to the main electronics suite. System installation and setup will be very close to the "plug and play" goal often sought after and seldom achieved in both simple and complex systems.

Contact Furuno USA, www.furuno.com.