The HELIX 7 DI is the Humminbird fish finder part number 409800-1. It’s one of the Humminbird models that have been discontinued and replaced by newer models, such as the HELIX 7 CHIRP DI G2. It’s a sonar-only fish finder featuring DualBeam Plus sonar and Down Imaging.
Key Features and Specifications
- Screen: 7″ diagonal, 256 color TFT, 800H x 480V pixel resolution, with backlight
- Sonar: Down Imaging, DualBeam Plus with SwitchFire
- Depth Capability:
- 350 feet (106 m) for Down Imaging
- 600 feet (183 m) on DualBeam Plus
- Frequency and Coverage:
- DualBeam Plus: 200 kHz / 28° and 455 kHz / 16°
- Down Imaging: 455 kHz / 75° and 800 kHz / 45°
- Transducer: Transom XNT 9 DI T
- Power Output: 500 Watts (RMS)
- Power Input: 10-20 VDC
- Power Draw: 800 mA
- GPS: No
- Maps: No
- Routes, Waypoints, Tracks: No
Control unit features and functions
Just like all the other units within the HELIX 7 series, this particular one features the same 7″, 800 x 480, 16:9 display. It also features LED backlight, but not only that, the display in all HELIX 7 (or above) units features a 50% more brightness. In other words, readability is much better, even during intense sunlight conditions. Also, since they offer a glass-bonded display, the glare effect is eliminated. So, with the HELIX 7 DI, you’ll have color TFT, super-bright imaging, glare-free, all in a medium-sized, 7-inch display.
The display also has an IPX7 water rating. This means the unit is not fully waterproof. However, it can withstand splashes, spills or any other incidental water exposure. It can actually survive immersions in freshwater, at depths of 1 meter, for up to 30 minutes.
This unit, along with all the other Humminbird fish finders in the HELIX 5 and 7 categories, does not include the superior processor that the HELIX 9,10 and 12 will have. However, the HELIX 7 units do have extra D-RAM. Therefore, navigation through menus and imaging refresh is faster.
The control unit of the HELIX 7 DI comes with the quick-release, gimbal mount. There’s also the option for an in-dash mount. The control unit also features an NMEA 0183 port, for extra connectivity options. However, since it doesn’t support GPS or mapping of any kind, it does not feature a microSD card slot, like the HELIX 7 DI GPS.
Sonar features and functions
Like most other units sold by Humminbird, the HELIX 7 DI model does include a transducer. The transducer that comes with the control unit is actually a DI dedicated model, the XNT 9 DI T. This transducer features a transom mount, and comes with 20′ (6 m) of cable, just about enough for the average bass boat. It also has a built-in temperature sensor, and this being said, the unit can monitor the temperature in the topwater substrate. The control unit does not offer a temperature graph function, though.
As mentioned above, this unit offers two distinctive types of sonar: standard 2D and Down Imaging. When it comes to Down Imaging, it can operate at two frequencies 455/800 kHz, using two thin beams fore to aft, but with side to side angles of 75° for 455 kHz, and more focused at 45°, for 800 kHz. Nonetheless, Down Imaging provides crystal-clear images, similar to the quality and aspect of a photo. This type of sonar is great for observing structure, vegetation, and assess the hardness of the bottom. Fish also appear on DI as white dots; but for detecting fish, and assessing their size, the 2D sonar helps a lot.
The traditional 2D sonar can also operate at two frequencies. This unit actually features DualBeam Plus sonar, which means the two 2D beams can be viewed together in split-screen, or even blended together. The 2D sonar uses conical beams though. For 200 kHz, the beam offers more coverage, with an angle of 28°. For 455 kHz you’ll get a narrower beam, of 16°, but a more detail.
This unit is not made for deep water use, and its internal sonar does not cover the 50 kHz frequency. Therefore an upgrade to a 50 kHz transducer it’s not viable. However, with the provided sonar and transducer, this unit can pierce through depths up to 600 ft with the 2D sonar, and up to 350 ft in Down Imaging.
The 2D sonar also features the Humminbird SwitchFire function. This allows you to quickly swap between two modes: Max Mode and Clear Mode. Max Mode quickly brings on-screen all the information that is caught by the transducer beam, great for observing your jig, and see as many targets as possible. On the other hand, Clear Mode removes all the clutter, focusing on the most important targets.
Of course, there are several sonar-related functions regarding the Humminbird HELIX 7 DI that should be mentioned here. First of all, there’s a Flasher mode for ice fishing, that provides the sonar information in a circular format. This offers a better use of the sonar in stationary mode, for example for ice fishing or down dropping from the boat. It has a steeper learning curve than the classic sonar view, but still, it’s not too difficult to learn how to use it.
Real-Time Sonar (RTS) and Bottom Lock are also two useful functions in certain situations. For example, RTS is a vertical flasher view, similar to the A-Scope function in the Garmin echo 551dv, which appears in the right side of the screen, providing the most recent information caught by the sonar. Bottom Lock is a function that continuously graphs the bottom regardless of depth. It’s a view that actually “flattens” the bottom, but it puts into view the fish next to it.
Evidently, like all the Humminbird units, the HELIX 7 DI has the FishID+ sonar mode. This actually a function great to have if you don’t like or you’re not familiar with the standard 2D view. It basically changes the fish arches in the 2D view with fish symbols of different colors and sizes, also reflecting their current depth.
There aren’t any actual drawbacks regarding this unit. The whole HELIX 7 series is actually brand new, with improved components. But even though the following aspects can’t actually be considered drawbacks, the HELIX 7 DI does have some lacks. First of all, it doesn’t have Sonar Recording, which is a neat function to have. Since there’s no microSD card reader, evidently the Screen Snapshot function in other units is not available in this unit, so you can only use Freeze Frame. Also, it does not offer a Temperature Graph function.
If you’re looking for a fish finder with Down Imaging, with a medium-sized display, but don’t want any GPS features, the HELIX 7 DI is definitely a fish finder to put on your list. It’s a unit that includes the transducer, and it’s currently under the mark of $400, a pretty decent and affordable fish finder.