Our last fishfinder (scanning sounder) review was about a year ago, in the December 2002 issue. In that article we covered six monochrome sounders priced under $400. This month we’ll look at four units equipped with color LCD screens. Why the change to color? Simple—they supply more information. A monochrome screen might be able to display four to eight different shades of black-gray-white that our eyes can recognize, while a color screen can show 16 or more distinguishable colors.
![Color LCD Fishfinders Under $1,000](https://cdn.practical-sailor.com/wp-content/uploads/2019/09/4902_Fish.jpg.optimal.jpg)
How does that additional information translate into an advantage for the user? Additional gradations on color screens make it easier to differentiate between hard and soft bottoms, protrusions on the bottom like ledges and wrecks, and other things that go bump in the night. If you’re a fisherman, they can help you tell the difference between your prey and a rock, and even sometimes distinguish between species of fish.
There’s another reason to go color: Their viewability has improved dramatically over the past few years. The latest color LCD screens, which utilize a Thin Film Transistor, can be read in any lighting condition.
What We Tested
Most electronic devices continue to improve as their prices drop—same goes for the color fishfinder. Today it’s common to find a technically refined color sounder with a speed- and temperature-capable transducer for under $1,000. Even selecting a more expensive thru-hull transducer will still keep you under the $1,000 mark on many units.
Our two selection criteria for this test provided that each unit must have a color LCD screen and be priced from $500 to $1,000. In fact, all the units we tested actually fall into a $700 to $900 range.
The four fishfinders we tested are the Furuno FCV-600L, the Garmin 320C, the Lowrance LCX-18C and the SI-TEX CVS-106L.
How We Tested
To make ongoing testing as consistent as possible, we set up this evaluation along the same lines as our previous monochrome sounder test.
A sounder is of little use if you can’t see the screen easily and clearly under all conditions. Hence, each machine was given two ratings for “viewability,” one for day and one for night. For the day rating, we viewed each machine on our test boat from a normal operating distance in full sunlight, shade, and with and without polarized sunglasses. The night rating was also done on the water in the test boat. All machines were operated simultaneously, side by side in simulator mode, and adjusted for the best possible display during each viewability test.
Performance testing was done in warm (85-90° F) salt water using the glassed-in thru-hull transducer installed in our test boat. It’s an Airmar Triducer capable of supplying speed and temperature in addition to sounder data. Temperature data was supplied and read by each machine and appeared accurate. The speed function wasn’t operative at the time of testing.
We used Airmar crossover cables as needed to connect the 10-pin cable end to each machine, one at a time. However, we were unable to obtain a crossover cable for the Lowrance unit and used the supplied transom-mount transducer for all testing of this unit.
Additionally, we tested each sounder with its supplied transducer to make sure transducer compatibility was not a performance issue. To preclude any interference from other machines, we operated only one unit at a time when conducting actual performance tests. This did not prevent the machines on other boats from interfering with our tests. If you look very closely, you can see the short vertical lines in a couple of photos, indicating our test unit picked up the signal of a nearby sounder.
All testing was done using 200 kHz. Since the machines are also 50 kHz capable, we tested each on this frequency during our deep-water test.
Testing was accomplished by making multiple passes with various configurations over known bottom structures in various depths. For example, in deep-water testing, we made several passes over a wreck using full screen, split screen with bottom lock or zoom, split screen with dual frequencies, full auto gain, and manually adjusted gain. This was done to obtain the best performance from each unit. The shallow-water test was done in 5′ to 25′ depths over a bottom with rapid depth changes and bottom structure. Mid-depth testing was done over a large steel ship sunk in 120′ of water. And the deep-water evaluation was carried out while drifting over a steel structure in 290′ of water. The units showing the cleanest detail were rated highest.
Each sounder was assigned a score for “ease of use.” The fewer references to the manual and the fewer button pushes required to carry out a function, the higher the score. If even simple functions required constant manual review or wading through multiple menus, scores were lower.
The warranty on each machine is listed in the accompanying table for both parts and labor costs for repairs.
We did not test the GPS mapping capability of the Lowrance unit. As in the past, our testing stuck with factors that influence the performance of each unit’s fishfinder.
Our test rig allowed for high-speed testing of all units except the Lowrance. (Because we were unable to obtain a crossover cable to connect our transducer to the Lowrance, we relied on our old set-up, using their transducer. Its construction only allows for slow-speed testing.)
All sounders performed adequately, and no rating was given for high-speed performance, which is of less interest to displacement-boat sailors, and which is primarily a function of transducer installation anyway.
We also didn’t rate ease of installation for the display units. All come with brackets, and all can be flush-mounted. Additional installation factors include the unit’s location on the vessel, the type of transducer, and the distance to appropriate electrical connections. Power consumption stated by the manufacturer for each unit was minimal, listed as 1.5 amperes or less for all machines.
Incidentally, it may seem strange for a device to demand so little power, yet be rated with an output of hundreds of watts. The reason lies at the heart of the sonar function: the power required is intermittent. Ted Gartner of Garmin explains it, via one of his engineers:
“The key is that ‘power’ is an instantaneous measurement, and the unit’s sonar transmission is not continuous. The sonar transmits 500 watts (or whatever) for a brief instant, and then doesn’t transmit anything for quite a while (while it listens for sonar echoes, processes data, shows images on the display, etc.). In effect, you have a short burst of 500W out, but then a relatively long period of zero watts out. Over time, this averages out to a very low power output.”
![Color LCD Fishfinders Under $1,000](https://cdn.practical-sailor.com/wp-content/uploads/2019/09/4902_Fish2.jpg.optimal.jpg)
Furuno FCV 600L
Furuno’s FCV 600L is a dual-frequency fishfinder rated at 350 watts. Data is displayed on a 5.6-inch 16-color LCD screen. Input voltages can vary from 12 to 24 volts DC. It’s packed with features, including A-Scope (which shows what’s directly under the transducer in real time), Bottom Lock, Variable Zoom, Range Shift, and eight adjustable ranges. Water Temperature and Speed are also available depending on the transducer selected.
The control panel has 14 pushbuttons, plus a cursor pad and a power button. We especially like the three sets of paired buttons marked for range, shift, and gain adjustments, with one button designated to increase the parameter and another to decrease it. The set-up allows the user to adjust these three controls quickly. We’d prefer a knob for gain control, but at least with a pair of switches you’re not pushing buttons all day to tweak the gain.
Other pushbuttons pull up an onscreen menu and require further input from the user for the final settings. An example is the “Brill” button. Pressing it brings up an onscreen menu. Via the cursor pad, the user can then select from 10 tone and eight brightness settings.
One quirk: At one setting below maximum brightness, we witnessed a slight flickering on the screen. It disappeared at brightness levels one to two notches lower.
The Furuno outperformed all others during our deep-water testing and showed as much or more detail than all others in our mid-water tests. Shallow water performance was rated excellent.
Bottom Line: Excellent performance puts the Furuno at the top of our list. We really like the crisp action of the pushbuttons and the paired sets allow easy access to several functions. Its screen does need to be a bit brighter for daylight viewing, in our opinion.
![Color LCD Fishfinders Under $1,000](https://cdn.practical-sailor.com/wp-content/uploads/2019/09/4902_Fish3.jpg.optimal.jpg)
Garmin 320C
The most compact unit in the group, the 320C has a bright 16-color, 5-inch screen. Garmin claims a power rating of 500 watts when the unit is used with its dual-frequency transducer and 400 watts with a single-frequency transducer. Input voltages from 10 to 35 volts DC are acceptable.
This machine is not as feature-laden as the Furuno, but still boasts Bottom Lock, Variable Zoom, 16 range settings, a single custom Range, plus Speed and Water Temperature.
Control of the 320C is handled via a power/backlight button, a cursor pad, and nine other pushbuttons. To access a feature or control, you push that button and a menu of items is displayed. Use the cursor pad to make your selection. For example, pressing the “Range” key will bring up a list of the 16 range settings, plus the auto and custom settings on a list. Now use the cursor to select the desired depth range, followed by the Enter key to execute. Another way to access features on the Garmin is with the cursor pad, pressing the right or left arrow scrolls through several functions. The name of the feature available for use will be displayed in the upper left corner of the screen. This does keep at least one feature readily available for adjustment simply by pressing the cursor pad. But this method of operation is not as good as having dedicated button control. It’s awfully nice to have fast, continuous access to things like gain, range, and shift control.
Daylight viewing of the Garmin is superb, the best of the bunch. Some very slight screen flickering was evident intermittently. Night viewing of the Garmin is also excellent; it has 13 levels of brightness available, though it does not range down as low as the Furuno in actual brightness.
Some operating features of the Garmin are not well documented in the owner’s manual. We had to speak to a Garmin engineer to get additional information on the brightness control and bottom lock. The Garmin performed well at the deep wreck, mid-depth, and shallow.
Bottom Line: A good performer with a great display screen—we rate it a close second behind the Furuno. It lacks a few features found in the Furuno, and it is not as easy to use.
Lowrance LCX-18C
The Lowrance LCX-18C operating manual claims a 256-color, 6-inch screen. We measured it at 5.75 inches diagonally. Lowrance manager of public relations and advertising, Steve Wegrzyn, explained the discrepancy: “Actually, the active area of the screen measures 5.66 inches diagonally. Just last year, we in marketing started rounding-up the diagonal measures for the same (or virtually the same) displays.”
This is the only unit that has a landscape-oriented screen, as opposed to portrait-oriented. Vertical screens show more of what’s under you; horizontal ones paint a larger picture of the area, although all of what you see is already behind you. While fishermen tend to like a vertical display for the density of information in a narrower column, there’s an argument that a horizontal display is preferable for sailors trying to pick a spot to drop the hook in an anchorage.
Claimed power output is 1,000 watts with a dual-frequency transducer and 375 watts with a single- frequency transducer. Acceptable input voltages are 10 to 15 volts DC. Sonar features include A-scope (FasTrack in Lowrance parlance), a readily accessible zoom, 16 range settings, speed, and water temperature. One feature available on the LCX unit, and not found on other units tested, is GPS mapping capability. It does require additional hardware, and we did not examine any GPS features.
Operation of the Lowrance is accomplished with a single power/light pushbutton, a cursor pad, and seven other pushbuttons. Most of the adjustments on this unit require loading the menu, line-selecting the item via the cursor, then adjusting the item, followed by Enter or Exit to execute the selection. Only one set of paired pushbuttons, the zoom-in and zoom-out buttons, are exempt from this cumbersome procedure.
The LCX screen is quite nice for daylight viewing, but suffers from a lack of brightness range at night. Even though it has 11 brightness and 21 contrast settings, it doesn’t dim nearly as low as the best machines. Intermittent minor screen flickering was also evident on the Lowrance.
Bottom Line: The screen needs a better brightness range for good nighttime viewing, and there’s a great deal of button-pushing required to access its features. Still, the GPS mapping capability and landscape displays will be attractive features for some.
SI-TEX CVS-106L
The CVS-106L has a 16-color 5.6-inch LCD screen and its manual claims a power output of 300 watts. Line input voltages between 10.8 and 31.2 volts DC are within specifications. It’s a feature-rich machine with A-Scope, Bottom Lock, Variable Zoom, Range Shift, and nine depth ranges. Speed and Temperature are also available.
The SI-TEX is controlled by eight two-position pushbuttons with a ninth designated as the power on/off switch. The SI-TEX has five separate buttons on its face to adjust gain, range, shift, variable range marker, and zoom. This gives the operator easy control of five oft-used adjustments. Good thinking, SI-TEX.
The LCD screen on the CVS-106L is rated good in daylight and fair at night. Its six-level brightness control has less than optimum range, and when viewed at night from an angle, the screen seems to wash out and get brighter. Performance was rated excellent in shallow water and good in both mid and deep water.
Bottom Line: For the money, this is a good machine—rated close behind the Furuno in performance. We like the five buttons for often-used adjustments, although the button action is not as clean as on the Furuno. Night viewing needs to be better, in our opinion.
Conclusions
Our top-rated unit, the Furuno FCV-600L, is fully functional in either of its two auto modes, but really shines when the available controls for gain, range, and shift are understood and used to enhance performance to its maximum. The Furuno tops the field for the second time—the Furuno LS6100 monochrome was rated best in our last test.
Our second choice is the Garmin 320C, a good performer with an excellent screen. The SI-TEX, while not on the level of the Furuno or Garmin, is still a good value. The Lowrance didn’t perform quite as well as our top two choices, but that’s not to say it did poorly, and its GPS capabilities and landscape display might tip the balance in its favor for many customers.
Also With This Article
Click here to view “Value Guide: Color Fishfinders Under $1,000.”
Click here to view “How Scanning Sonars Work.”
Contacts
• Airmar Technology Corp., 603/673-9570, www.airmar.com
• Furuno USA, Inc., 360/834-9300, www.furuno.com
• Garmin International Inc., 913/397-8200, www.garmin.com
• Lowrance Electronics, 800/324-1356, www.lowrance.com
• SI-TEX Marine Electronics Inc., 727/576-5734, www.si-tex.com