The HELIX 8 CHIRP MEGA SI+ GPS G4N is one of the Humminbird fish finders released in 2020. As opposed to the older version, the HELIX 8 CHIRP MEGA SI+ GPS G3N, it comes with a few extra features. For example, it has built-in WiFi, built-in NMEA 2000, and is compatible with the new CoastMaster charts. For reference, this is the Humminbird part number 411350-1.
Key Features and Specifications
- Display: 8″ diagonal, 1024H x 600V pixel resolution, WVGA 16-bit color TFT, with LED backlight
- Sonar: Dual Spectrum CHIRP, CHIRP MEGA Side Imaging+, MEGA Down Imaging+
- Frequencies supported: 50/83/200/455/800/1200 kHz
- Transducer: Transom XM 9 HW MSI T
- Beam coverage:
Dual Spectrum CHIRP: 25°, 42°
Down Imaging: 45°, 75°
Side Imaging: 800 ft. (244 m), 250 ft. (76 m), 400 ft. (122 m)
- Max. Depth Capability (with the included transducer):
Dual Spectrum CHIRP: 1,200 ft. (365 m)
Down Imaging: 400 ft. (122 m)
Side Imaging: 125 ft. (38 m)
- Power Output: 1,000 Watts (RMS)
- Power Input: 10.8-20V DC
- Power Draw: 1 Amp
- GPS: 10 Hz, internal
- Cartography: Humminbird Basemap
- Routes, Waypoints, Tracks: 47; 2,750; 50 (20,000 points each)
Sonar and transducer
This Humminbird fish finder offers three sonar technologies; these are Dual Spectrum CHIRP, MEGA Down Imaging+, and MEGA Side Imaging+. It supports multiple base frequencies, including 50/83/200 kHz for standard CHIRP, and 455/800/1200 kHz for structure scanning. It also supports MEGA 360 sonar.
The transducer included with the unit is the XM 9 HW MSI T. This transducer supports all three sonar technologies built-in the unit. It has a metallic transom mount, 20 ft. (6 m) of cable, and a built-in temperature sensor.
For Dual Spectrum CHIRP, the transducer uses conical beams. There are three modes that it can work with; these are Full Mode, Wide Mode, and Narrow Mode. For the Wide Mode, the CHIRP range is 140-200 kHz while the beam coverage is 42°. The Narrow Mode beam operates in a 180-240 kHz CHIRP range and the beam has a coverage of 25°. And finally, the Full Mode is for using the complete frequency range. The maximum depth capability that the transducer can reach when using the Dual Spectrum CHIRP sonar is 1,200 ft. (365 m).
For Down Imaging, the transducer uses oval, thin beams. At 435-535 kHz and 1100-1200 kHz, the beam coverage is 75°, while the 800-860 kHz beam has a coverage of 45°. Needless to say, the MEGA DI+ plus mode (1100-1200 kHz) offers the best imaging quality. The greatest depth that the Down Imaging sonar can reach is 400 ft. (122 m) when using the 455 kHz beam, while the MEGA DI+ beam can reach depths up to 200 ft. (61 m).
For Side Imaging, the XM 9 HW MSI T transducer also uses three CHIRP frequency ranges. At 440-500 kHz, the side beams offer a total coverage of 800 ft (244 m); at 790-850 kHz, the total side to side coverage is 250 ft. (76 m). And finally, the MEGA SI+ mode at 1075-1150 kHz offers a total side to side coverage of 400 ft. (122 m).
The unit offers an impressive range of standard sonar features. The list includes Selective Fish ID, Amplitude Scope, Circular Flasher, Sonar Zoom, Bottom Lock, SwitchFire, WhiteLine, and more. It also has Sonar Recording and a Temperature Graph feature.
As its name suggests, the Humminbird HELIX 8 CHIRP MEGA SI+ GPS G4N has built-in GPS. It is equipped with a 10 Hz GPS receiver which means that it can provide position updates 10 times per second. Enhanced GPS fixes can be obtained using information from EGNOS, WAAS, or MSAS. The unit also has a GPS speed function so it can calculate the speed of your boat by using the GPS data.
Waypoint creation, route creation, and track plotting features are also available with this Humminbird model. The unit can save up to 2,750 waypoints in its memory and you can customize them with various icons to make them more suggestive. It can also save up to 47 routes with 50 waypoints per route, and record up to 50 tracks with up to 20,000 points each.
In terms of charts, the unit comes with the Humminbird Basemap platform which is pretty much standard for most Humminbird GPS units. These charts combine data from Humminbird, NOAA, and other trusted cartography sources. They cover more than 10,000 U.S. inland lakes with 1-foot contours, while for the blue waters, they offer precise data for the entire U.S. coast, showing buoys, hazards, hotels, marinas, daymarkers, depth markings, spot soundings, and more.
The AutoChart Live feature is also available with this Humminbird unit. This application uses the GPS and CHIRP sonar data for scanning and revealing the depth contours of any lake or body of water. Therefore, if the Humminbird Basemaps don’t offer enough detail for your favorite lake, you can always map it yourself.
Among other navigation features, we can mention the external GPS and AIS support. Also, this unit supports various other add-on technologies such as Minn Kota i-Pilot Link, Talon and Raptor shallow water anchors, and even Humminbird CHIRP Radar.
Control unit features
The Humminbird HELIX 8 CHIRP MEGA SI+ GPS G4N features an 8-inch display with a rich pixel resolution of 1024H x 600V, with LED backlight for improved readability at night and in direct sunlight. It doesn’t have touchscreen technology like the SOLIX units, so the navigation through the menus and the usage of its functions is done exclusively from its keypad. It is also IPX7 waterproof, which essentially means that it’s tight enough to withstand incidental water exposure and rain.
The unit offers multiple networking possibilities. To begin with, it has built-in NMEA 2000 and Ethernet. Therefore, you can easily connect it to an already existent boat network or connect other boating instruments to it. It supports Humminbird Radar, i-Pilot Link, external GPS, and AIS. Also, all the HELIX G4N models have actually been designed to work seamlessly with the One-Boat Network.
WiFi and Bluetooth wireless technologies are also included with this unit. This being said, you can sync your Humminbird chartplotter with your smartphone or tablet by the means of the FishSmart app. This allows you to easily download software updates, maps, control Raptor or Talon anchors from your chartplotter, and even receive smart notifications from your phone. You can also pair your chartplotter with an RC2 remote control for wireless usage.
Last but not least, the unit has two microSD card slots. Therefore, you can use two cards simultaneously, for example, one with Navionics charts, the other one blank for saving data.
- Dual Spectrum CHIRP;
- MEGA DI+;
- MEGA SI+
- XM 9 HW MSI T transducer included;
- Depth capability up to 1,200 ft with the included transducer;
- Supports 50 kHz;
- Multiple sonar functions available, such as A-Scope, Bottom Lock, WhiteLine, Fish ID+, Alarms, SwitchFire etc;
- Sonar Recording and Screen Snapshot functions;
- 10 Hz internal GPS;
- Humminbird Basemap chart platform built-in;
- AutoChart Live included;
- Supports Navionics+, Navionics Platinum+, LakeMaster Plus, CoastMaster, and SmartStrike charts;
- Trackplotting, routes and waypoints functions;
- Large display with a resolution of 1024 x 600 for crisp imaging;
- IPX7 waterproof;
- Built-in NMEA 2000 and Ethernet;
- Wi-Fi and Bluetooth connectivity;
- Compatible with the FishSmart App and the RC Bluetooth remote controls;
- Supports Radar, I-Pilot Link, Talon and Raptor anchors, Cannon Downriggers, and One-Boat Networks;
- Supports AIS and GPS heading sensors;
- Dual microSD card reader;
- Upgradeable internal software;
- Gimbal mount included;
- Fairly easy to install.
- In-dash mount is not included;
- Unit cover is not included;
- Remote control is not included.
The Humminbird HELIX 8 CHIRP MEGA SI+ GPS G4N is a fish finder and chartplotter featuring Dual Spectrum CHIRP sonar, MEGA DI+ sonar, MEGA SI+ sonar GPS, Humminbird Basemaps, AutoChart Live, superior networking features such as Ethernet and NMEA 2000, as well as wireless connectivity (Bluetooth and Wi-Fi). It also includes the XM 9 HW MSI T for both 2D CHIRP and structure scanning. It’s a pretty complete unit, great for a wide range of boats, for both off-shore and inland fishing.