The Humminbird 678c HD is currently the most basic fish finder in the 600 series. It’s also the cheapest one, but despite the fact it doesn’t support any navigational features or superior sonar technology such as Side Imaging, Down Imaging or 360 Imaging, this model still is quite a reliable one.
Just like the other units in the 600 series, the 678c HD comes with a 5-inch diagonal display, 480 x 640 pixel resolution, full color TFT and backlit screen. The head unit comes with the standard Quick Disconnect Mounting Kit, but can be fixed on your boat with an In-Dash Mounting Kit. Has a power output of 500 Watts RMS / 4,000 Watts PTP, with a depth capability for 1,500 ft.
Regarding its sonar capabilities, this fish finder has Dual Beam Plus sonar, that can be operated at two frequencies: 83 kHz with a 60° beam, for a wider coverage, and 200 kHz with a 20° beam for a narrower but more accurate sonar scan. The standard transducer of the 678c HD fish finder is the Transom XNT 9 20 T. SwitchFire and Fish ID + view options are also included.
Although for other units the PC connect feature is optional, this fish finder has it included.