Humminbird 798ci HD SI Combo Review

  • Display
  • Sonar
  • GPS
  • Ease of use
  • Price

There are great fish finders on the market. And then there is the Humminbird 798ci HD SI Combo. This is an incredibly advanced unit right towards the top of the Humminbird range that has superb features attached to it. Not only is the unit able to read to great depths with incredible accuracy, it also has an excellent transducer attached to it and it is all shown on an excellent screen that that high detail and resolution. If you are in the market for a premium fish finder, then this may well be the unit for you.


Humminbird 798ci HD SI Combo ReviewThe Screen

A legible and clear screen is exactly what you want when angling and this is a feature that the 798ci HD SI most certainly has. The screen is some 5 inches point to point and has an excellent resolution of 640 x 640 pixels which gives incredible detail from any angle you view it from.

There is also a split screen feature where you can display multiple navigation information or multiple sonar information on the same screen, which is incredibly useful and saves you from flicking in-between the two. Alongside where the fish are located you can display your exact location on the map or thermoclines in the water, which is another way of opening up the world below you.

The lighting for the unit is also excellent, allowing you to view it from just about any angle clearly. There are over 256 colours which also aids the level of detail.

Humminbird 798ci HD SI sonarThe Sonar

The unit comes equipped with a sonar unit capable of scanning at 2 frequencies and these are 83 kHz and 200 kHz, depending upon just what you want to scan. There is very little interference shown on the sonar scans due to the high quality of the unit and it has a scanning arc of 20 degrees at 200 kHz and 60 degrees at 83 kHz. Side Imaging and Down Imaging is also used so that you get a 360 degrees picture of what is below you, a feature Humminbird are incredibly proud of.

There are several features built into the sonar unit also so that you get the best picture possible. These include a range of screen modes, from clear mode to max mode that can either enhance the detail or range of your scans. The depth reading ability of the unit should also be noted, as it can scan down to some 1,500 ft which makes it suitable for virtually any body of water you will be traversing.


The Transducer

As with most higher end Humminbird products the transducer is a great unit and does its job perfectly. It reads thermoclines within the water incredibly well and displays them upon the screen very accurately, which all helps in the bigger picture towards refining your catch. It can be fitted to either your transom or the inside of your hull, all dependant upon where you have the space.

GPS Capabilities

There is a precision in-built GPS antenna that should suit your needs although an internal one may be installed to upon the unit. This GPS can be used in collaboration with the built in Unimap cartography of the coastlines and waterways of the United States to gain an incredibly powerful navigation tool. There is also a 3D chart tool.

As with other units, navigation of routes and waypoint plotting is also capable with this device. Once a favoured route has been chosen, you will be able to retrace it as many points as you wish. 50 unique routes can be saved and over 20,000 waypoints can be stored, giving you an even more detailed view into your waterways both local and nationally.

Humminbird 798ci HD SI featuresOther Usability Features

An easy to navigate and use unit is incredibly important and this is an aspect the 798ci HD SI does incredibly well in. Menus have been designed to be legible and simple in nature, and the buttons also describe what they do via the sticker above them or their function is obvious. The unit draws power just like others in its field, and the design is solid and good to the touch also, with nice rounded edges that help keep everything in shape.

There is also 2 SD card slots available either side of the unit, which allows you to download multiple cartography to show alongside what comes installed on the unit. This enhances the coverage of the unit immensely. Is there one aspect you feel a particular map is missing? Simply switch over to one of your SD card maps to fill the gap!



  • The unit is good value for money with these features included
  • Robust
  • Excellent sonar scanning abilities
  • Good fish locating software
  • Great transducer
  • Crystal clear screen


  • There are one or two too many buttons present upon the interface making it look somewhat cluttered
  • Initial set up is a little technical



The 798ci HD SI is an impressive unit whichever way you look at it. It combines some of the best features in the Humminbird range with great usability, ensuring that will be able to find and catch fish in little to no time at all. Its a good price, it has a great screen and is ideal for somewhat experienced to fully experienced anglers. If you can, ensure that this is the fish finder you purchase. I hope that this Humminbird 978ci HD SI review has been helpful.