GPSMAP 840xs is a part of the new series of fishfinders from Garmin that support down imaging as well as side imaging (Garmin branded those technologies as DownVü and SideVü). Down imaging is built-in while side imaging requires a GCV 10 module that is sold separately. The 840xs has an 8 inch keyed display and comes preloaded with BlueChart G2 coastal maps as well U.S. LakeVü maps. There is also 8 inch 820xs that doesn’t have BlueChart and LakeVü and 10 inch display versions – 1040xs and 1020xs, with and without maps.
Garmin GPSMAP 840xs comes with a 500W, dual beam 77/200 kHz, transom-mounted transducer that supports traditional broadband sonar, CHIRP and DownVü. 600W CHIRP transducers and 1000W 50/200 kHz dual frequency transducers are also supported and can be purchased separately. CHIRP will give you the most detailed, crystal clear output even at higher speeds. You can suppress sonar noise to achieve remarkable target resolution while reaching greater depth. The 840xs has a maximum depth of 1750 feet with the 500W Garmin dual frequency transducer, and a depth of 2700 feet with the 1kW Airmar B260 transducer.
The included LakeVü cartography contains 17,000 U.S. lakes. The GPS refresh rate is 10 kHZ which results in virtually fluid display. The 840xs is Garmin Radar compatible. The NMEA 2000 support offered by the 840xs allows the user to connect it to other devices such as autopilot or SiriusXM Weather radar, keeping you up to date on rapidly changing conditions. While pricy at $1500, the GPSMAP 840xs includes a lot of bang for the buck. Anyone interested in the unit can expect to see it on the market in February of 2014. You can get a great deal on Garmin GPSMAP 840xs here.
| Lowrance HDS-7 Touch Insight | Humminbird 999ci HD SI | Garmin GPSMAP 840xs | |
|---|---|---|---|
 |  | | |
| Screen Size | 7 in | 8 in | 8 in |
| Screen Resolution | 480 x 800 pixels | 480 x 800 pixels | 600 x 800 pixels |
| Display Type | Widescreen, 16:9 ; WVGA color TFT LCD | 16:9 Color | color SVGA |
| Touchscreen | Yes | No | No |
| Imaging | 2D, DownScan, StructureScan, Downscan Overlay | 2D, Down Imaging, Side Imaging | 2D, Down Imaging (Side Imaging available with GVC box sold separately) |
| Transducer Type | Transom Mount/Trolling Motor | Transom Mount/Trolling Motor | Transom Mount/Trolling Motor |
| Transmit Power | 31W Broadband RMS (analog equivalent 3200W) 250W Broadband Peak-to-Peak (analog equivalent 30,000W) | 1000W RMS 8000W Peak-to-Peak | 1 kW traditional 600 W CHIRP |
| Sonar Frequency | (50/200 or 83/200 kHz) + 455/800 kHz | 83/200 kHz 2D 455/800 kHz Side Imaging | 77/200 kHz 2D Also supports 50/200 dual frequency transducers |
| Maximum Depth | 5000 ft / 1524 m | 1500 ft 2D 150 ft Side Imaging | 1,750 ft @ 50 kHz, saltwater, Garmin dual freq transducer @ 500 W 2,700 ft @ 50 kHz, saltwater, Airmar B260 transducer @ 1000 W |
| GPS Antenna Type | Internal, high-sensitivity GPS+WAAS | Internal | Internal |
| Waypoint Storage | 5000 | 3000 | 500 |
| Routes | 200 | 50 | 100 |
| Plot Trails | 10 tracks, 12,000 points | 50 tracks, 20,000 points | 50 tracks, 50,000 points |
| Default Maps | Expanded U.S. BaseMap or Insight USA | Humminbird ContourXD | U.S. LakeVu and BlueChart g2 coastal maps |
| MSRP | $1549 | $1499 | $1499 |
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