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Northstar Explorer 660 Review

The Northstar Explorer 660, a standalone chartplotter fishfinder, is packaged with the display unit, a GPS antenna, and a dual-frequency transom-mount transducer.

Outside the US this unit was also marketed as the Navman Trackfish 6600 and that is the unit we actually tested. That is no longer the case though as Navico has decided to drop the Navman brand, effective mid-March 2008.

northstar explorer 660 chartplotter fishfinder

Northstar 660

We mounted the display unit, which measures about 8 inches square by 3 inches deep, on our test boat temporarily using the accompanying swivel bracket.

If you need the ability to swivel the display the bracket is nice, but we found it a little wobbly side to side. We’d prefer to flush mount using the supplied hardware and threaded bushings in the rear panel.

Electrical connections to the Explorer 660 display are all made with color-coded factory-installed twist-lock connectors.

Screen Size and Viewability

The Northstar Explorer 660 screen is nearly 7 inches on the diagonal but this measurement belies its true size. The very high-resolution screen, with an 800 by 480 pixel count, measures more than 6 inches tall, about the same height as the average 10-inch display. This makes for an impressive sounder or chart view in full-screen mode.

Fifteen levels of the brightness control took the Explorer 660 screen from one of the brightest in daylight to the darkest at nighttime. We were impressed and rate it excellent for daylight viewing and good at night.

One quirk we noticed at night was a loss of detail in the map area when viewed from angles on the right. This loss of detail did not take place when we looked at angles from the left side.


Easy access to a well-laid-out main menu as well as numerous page specific menus make the Northstar Explorer 660 very easy to operate. Saving waypoints from the map page is a snap, just push the enter key twice. Routes can be built easily from the map page too. Move the cursor to the first spot, hit enter, and continue until you reach your destination. One weakness we noticed are the short waypoint names, they are only allotted 8 characters.

Other operational highlights include split-screen sizes that can be quickly adjusted to any portion of the screen from 20 to 80 percent. Another is a data page with 8 user-selectable boxes that we could see well from over 10 feet away from the display.

northstar explorer 660 sounder view

Marking a small school of fish on the Northstar Explorer 660.


When using the Explorer 660 in sounder mode, the tall display screen really shows its stuff. It has almost twice the screen space devoted to showing the water column than similarly sized units with a landscape layout.

The unit’s 600-watt sounder features auto zoom, marker zoom, bottom discrimination, and a full-color A-scope. The A-scope function on the Explorer is taken to the next level as it can be displayed over as much as 80 percent of the screen width and used for manual gain adjustment. Though the Explorer 660 sounder lacks a few functions like shift and a full-height bottom lock, it more than makes up for this with its easy use and crisp large screen. We rated the fishfinder excellent for both presentation and usability.

Odds and Ends

The Explorer 660 has the ability to function as a fuel computer when connected to an appropriate fuel flow sender, it is also SmartCraft compatible. Although it has an internal map, using a C-Map NT or NT MAX chart card can enhance cartography.

This Northstar unit sports a 2-year parts and labor warranty.

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Final Thoughts

We really like the Northstar 660 because of its extremely crisp high-resolution screen and powerful yet user-friendly software.