In case you don’t want to spend extra on a unit that also has GPS, but you happen to be interested in a medium-sized unit, with Down Imaging, the HELIX 7 DI is exactly the model you’ve been looking for. It has pretty much the same features as the HELIX 7 DI GPS, only without the GPS, and a few other functions. Evidently, it also costs cca $80 less than the aforementioned unit. Anyway, let’s see what this unit can do for you.
First of all, as its name suggests, it’s a unit that has Down Imaging. And the Down Imaging provided by this unit is actually a dedicated one, being able to support 455/800 kHz. The sonar on the HELIX 7 SI GPS for example, can only support 455 kHz, and its DI beam is made from the side beams. This being said, the Down Imaging sonar provided by this unit, just as in the GPS model, offers crystal clear imaging, with photo-like clarity, excellent for determining the shape of structure and bottom. Down Imaging can operate in two, fan-shaped, thin beams with a side-to-side angle of 75° for 445kHz and 45° for 800 kHz.
The unit also features DualBeam Plus sonar, which means the 2D, traditional sonar mode also can operate at two frequencies: 200 kHz, with a beam of 28°, and 455 kHz with a narrow beam of 16°. The 2D sonar beams are conical though, not razor thin, fan-shaped like the DI beams. The 2D views can be observed in split-screen simultaneously, or even blended together.
The unit’s depth capability is 350 ft for DI, and 600 ft for 2D.
In terms of sonar, this unit also offers several other related and useful functions. Some of them are SwitchFire, Split-Zoom, Fish ID+ and Bottom Lock.
Like most Humminbird units, this one also includes the transducer that supports all the mentioned frequencies. It’s actually the XNT 9 DI T, with a transom mount. The transducer also has a built-in temperature sensor. The unit does not offer the Temperature Graph function though.
When it comes to the control unit features and functions, to begin with, it has a 7-inch display, with an 800 x 480 pixel matrix and 16:9 display. Since it’s a HELIX unit, it has 2XRAM more than previous other units, such as the ones in the 600 series. This means faster refresh. Evidently, it has has a TFT 256 color display, with LED backlight.
Its water rating it’s IPX7, which means it can withstand incidental water exposure.
The HELIX 7 DI comes with a gimbal, tilt and swivel mount. It has a NMEA 0183 port, but does not feature Sonar Recording, not has an SD card slots. And just to be clear, it does not support any type of GPS.