Chart Your Course The GPSMAP 178C features a built-in worldwide marine basemap and accepts BlueChart® offshore marine cartography, featuring detailed depth contours, inter-tidal zones, wrecks, navaids, and many other points of interest. For small-water anglers, the 178C is compatible with MapSource Recreational Lakes with Fishing Hot Spots, featuring fishing areas, boat ramps, marinas, and hazards for hundreds of popular U.S. and Canadian lakes. You can use compatible preprogrammed data cards, which insert easily into the slot on the front of the plotter.
Catch Some Fish The 178C comes with a built-in sounder with Garmin’s exclusive See-Thru® fish targeting technology. The sounder features adjustable range, gain, zoom and bottom lock. It also has new digital display technology that offers an easy-to-read, semi-transparent digital readout so you can see sonar images "behind" the data.
GPSMAP 178C Sounder: Leaves fish with nowhere to hide Physical & Performance: | Unit dimensions, WxHxD: | 6.3" x 4.9" x 2.8" (16.0 x 12.5 x 7.1 cm) | Display size, WxH: | 3.2" x 3.2" (8.1 x 8.1 cm) | Display resolution, WxH: | 320 x 320 pixels | Display type: | 256-color CSTN | Weight: | 1.2 lb (553 g) | Waterproof: | yes (IPX7) | RoHS version available: | no | Maps & Memory: | Basemap: | yes | Preloaded maps: | no | Ability to add maps: | yes | Accepts data cards: | Garmin data cards | Waypoints/favorites/locations: | 3,000 | Routes: | 50 | Features: | CANet® compatible: | no | Supports AIS (tracks target ships' position): | no | Supports DSC (displays position data from DSC capable VHF radio): | yes | Audible alarms: | yes | Tide tables: | yes | Sun and moon information: | yes | 3D map view: | no | Dual-frequency sonar capable: | yes | Dual-beam sonar capable : | no | Split-screen zoom: | yes | Split-screen sonar/gps: | yes | Ultrascroll™ (displays fish targets at higher boat speeds): | no | See-thru® technology (exposes fish hidden in cover): | yes | Fish Symbol ID (helps identify fish targets): | yes | AutoGain Technology (minimizes clutter, maximizes targets): | no | Whiteline (indicates hard or soft bottom): | yes | Adjustable depth line (measures depth of underwater objects): | yes | A-scope (real time display of fish passing through transducer beam): | no | Bottom lock (shows return from the bottom up): | yes | Water temperature log and graph: | yes | Water temperature sensor included: | no | Other: | Frequency: | 200 kHz | Transmit power: | 400 W (RMS), 3200 W (peak to peak) | Voltage range: | 8-35 | Maximum depth: | 900 ft | Cone angle: | 20 degrees | |