Furuno FCV588

The Furuno FCV588 is the bigger brother of the FCV-628 model. It basically offers the same features, however, it’s a larger unit with an 8.4″ diagonal display. Although it’s a pretty old unit, it is still available in 2020. It does not have a built-in GPS system or charts, but can be interfaced with a chartplotter, so you can mark fishing spots on maps and other points of interest.

Key Features and Specifications

• Screen: 8.4″ diagonal, 480H x 640V pixel resolution, color TFT, with LED backlight
• Sonar: Dual frequency 2D sonar
• Depth capability: Depends on the transducer
• Frequency: 50/200 kHz
• Transducer: Not included
• Power Input: 12-24 VDC, 10-0.5A
• GPS: No
• Charts: No

Sonar features

This Furuno fish finder can operate at two frequencies: 50 kHz and 200 kHz. A transducer is not included with the unit, but there are several options available. We’ll list all these transducer options in the section below.

Due to the fact that the unit is capable of operating at frequencies as low as 50 kHz, it’s great for fishing in deep water. Depending on the transducer, it can reach depths up to 1,200 m (3,937 ft).

The Furuno FCV588 is a dual-frequency fish finder. In other words, it can use both sonar frequencies simultaneously if paired with a dual-beam transducer, and the returns from both beams can be observed and compared in split-screen.

The unit doesn’t have CHIRP technology such as the Lowrance Elite-9 Ti or the Raymarine Axiom 9 but does offer similar sonar technology. It’s the RezBoost revolutionary signal processing developed by Furuno which can achieve CHIRP-like performance. The imagery provided by the Furuno’s RezBoost sonar technology is up to 8 times clearer than the standard sonar of most other fish finders. This results in clearer visuals, higher resolution, and also improves the ACCU-FISH feature.

The unit offers several other, very useful fish finding features. Among them, we can count ACCU-FISH, Bottom Lock, Bottom Discrimination, White Line, A-Scope, and various alarms. Here’s a short presentation for each one of these functions.

ACCU-FISH is a feature specific to the Furuno units. It’s a function similar to the Selective Fish ID+ found in most Humminbird fish finders. However, there are several differences between ACCU-FISH and Fish ID. To begin with, ACCU-FISH measures the length of each fish hit by the sonar beam and then marks it on the display with a corresponding fish icon. This function also allows you to choose between depth and size to be specified next to each fish symbol.

Bottom Lock is also a feature offered by many other types of fish finders. It allows you to set up a depth interval beginning at the bottom and up, and enable a part of the image on the display to remain in that particular interval. In other words, it lets you keep an eye on the bottom at all times. The bottom range for this unit can be varied between 10-30 feet from the bottom.

Bottom Discrimination is a feature that provides bottom composition recognition. Depending on the intensity of the sonar echo, it can detect between Rocks, Gravel, Sand, and Mud, each type of bottom having a specific graphical display.

A-Scope (or Amplitude Scope) is a feature offered by most other fish finders; it’s a vertical flasher sonar that shows the most recent sonar echo. For this unit, it appears on the right side of the normal sonar view.

White Line is a feature that gives you the possibility to view the top edge of the bottom echo in white, in order to discriminate better between fish, structure, and the bottom.

Finally, in terms of alarms, the Furuno FCV588 offers 8 in number. There are 6 alarms for fishing, and 2 for navigation. These are the ACCU-FISH alarm, bottom fish alarm, fish school alarm, water temperature alarm, bottom type alarm, bottom alarm, speed alarm, and arrival alarm. Some of these require an extra sensor to be connected to the unit, or interfacing with a GPS navigator.

Recommended transducers

The Furuno FCV588 does not include a transducer. However, it’s compatible with several 600w or 1kW transducer models.

The 600w transducer list includes the following models: 520-5PSD, 520-5MSD, 520-PLD, 525-5PWD, 525T-PWD, 525T-BSD, 525STID-MSD, 525STID-PWD, 525T-LTD/12, 525T-LTD/20, SS60-SLTD/12, SS60-SLTD/20.

The 1kW transducers compatible with this unit are the 50/200-1T, 526TID-HDD. The 50/200-1T requires the MB-1100 matching box for connection to the unit.

Now, from all these transducers, the 600w 525STID-PWD model would seem to stand out as the most preferred by anglers. It’s actually a TRIDUCER, as it includes the 50/200 kHz transducer, a temperature sensor, and a speed sensor. It’s also capable of RezBoost, ACCU-FISH, and all the other functions offered by this unit.

The 525STID-PWD transducer uses two conical beams, 45° @ 50 kHz and 11° @ 200 kHz. With it equipped, this Furuno fish finder can reach depths of 1,200′ (353 m) when using the 50 kHz beam. As an alternative to the 525STID-PWD, you can also use the Airmar P66 which is basically the same, being also RezBoost capable.

Control unit features

The Furuno FCV588 fish finder features the same vertical layout as the FCV-628 model. However, it has a much larger display, 8.4″ in diagonal, with a pixel resolution of 480H x 640V, VGA, full color. It has LED backlight, and it’s IPX56 waterproof, which means it can withstand incidental water exposure and rain.

The unit has a TLL (Target Lat/Lon) output and you can interface it with a Furuno chart plotter, so that you can mark fishing grounds with various information (L/L, Depth, Water Temp, Fish size and Bottom type). It also offers NMEA 0183 support and can be integrated into this type of network. An NMEA cable is not included, though.

The unit doesn’t have touchscreen technology. It’s keypad operated, the navigation through the menus, and the usage of its functions is done exclusively via the keypad on the right. The language pack available for this unit includes the following languages: English, French, German, Spanish, Portuguese, Polish, Greek, Italian, Danish, Norwegian, Swedish, Finnish, Chinese, Thai, Vietnamese, Japanese, Burmese, and Indonesian.

In case you’re wondering, this Furuno depth finder does not have a microSD card slot, nor does it have a sonar recording function.

Last but not least, the unit comes with two mounts, the classic bracket mount, and the flush mount.

The Pros

• Low/High frequency sonar, capable of operating at 50/200 kHz;
• RezBoost technology – providing CHIRP-like imaging;
• Numerous useful fish finding functions available, including ACCU-FISH, Bottom Discrimination, Bottom Lock, White Line, A-Scope, Temperature Graph, 8 types of alarms etc;
• Interfaceable with Furuno chart plotters for marking Lat/Lon waypoints;
• IPX56 waterproof;
• Vertical display layout for a better view of the fish in the water column scanned by the transducer;
• Bracket mount included;
• Flush mount included;
• Fairly easy to install.

The Cons

• Transducer is not included.
• No GPS and navigation;
• No sonar recording function;
• No structure scanning sonar.

Bottom Line

The Furuno FCV588 is a sonar-only fish finder unit without any navigation functions (no GPS, no charts). It has only dual frequency 2D sonar capable of 50/200 kHz frequencies. It offers several sonar features including RezBoost, ACCU-FiSH, Bottom Line, Bottom Discrimination, White Line, and more. However, a transducer is not included with this unit.

Due to its 50 kHz capability, this Furuno fish finder is great for deepwater fishing, especially off-shore. Finally, it’s not exactly affordable for a unit without any navigation features or structure scanning sonar, but many anglers choose it over the more inclusive other units due to its reliability and high functionality.