The Garmin 740s is a standalone MFD that features a 7-inch display with touchscreen interface, an internal high-sensitivity GPS receiver, and a 1000-watt digital sounder into a single unit that comes preloaded with Garmin BlueChart g2 U.S. Coastal cartography that includes Bahamas coverage.
The back panel has four connectors, one for an optional external GPS sensor, a second for the power/data cable, a radar network plug, and a NEMA 2000 port. The 740s will interface with a number of Garmin radar units but is not network capable.
It can communicate with certain other devices like AIS or a satellite weather receiver via NEMA 2000 and say a VHF radio using NEMA 0183. Interfacing the 740s with an N2K network would require additional hardware.
The 740s package ships with the display unit, a protective front panel cover, mounting bracket, power/NEMA 0183 cable, owner’s manual, quick reference guide, and installation instructions.
For my review I mounted the unit using accompanying bracket. Removable bezels at the top and bottom of the display front yield access to flush mounting holes in the case. All you’ll need to complete a flush panel mount are screws.s
Garmin 740
Screen Size and Viewability
The 740s screen uses a landscape layout that measures 6-inches wide by 3.7-inches high yielding a 7-inch screen size when measured on the diagonal. Pixel count is a very high 800 by 480.
We rated day viewability on the high resolution Garmin display screen excellent while noting a bit of reflectivity. With its high resolution even fine details are sharp and clearly readable. When viewed using polarized sunglasses the screen darkened little and was readable even at extreme side angles. No screen fogging was apparent in the display at anytime during our review.
The 740s has an automatic backlight control system that uses a sensor on the front of the display to set screen brightness and color mode based on ambient light levels. The color mode options are a day or night color palette. The night palette uses darker coloration to enhance night viewing. In my testing the automatic system worked very well at matching the screen to the outside light. I rated the 740s excellent for night viewability.
Operation
This Garmin is unlike any other standalone chartplotter combo in their lineup. It finally brings together the easy-to-use touchscreen interface first launched on the expensive big screen MFDs down to a more affordable machine.
The Garmin 740s chart page can be viewed in perspective 3D, fishing, or as a traditional 2D navigation chart as seen here. . Note the course indicator line set for three minutes.
There is only one button on the face of the Garmin 740s and its main function is to turn the unit on or off.
All other user input is accomplished by touching an onscreen field.
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From the Home page you’d select from an option list of main pages.
The basic list includes the Chart, Combinations, Configure, Mark, Where To, Information, and Man Overboard.
If you hook up the transducer a Sounder page will show up too.
With certain optional accessories installed you’d also see a Radar and Weather page. Each main page has more menu items, again all based on the equipment installed, to select and execute related options. For example, pressing the Where To field brings you to its menu page where you’ll find options to view the waypoint list, route list, tracks, or offshore services. You can also search by name or stop navigation from this menu.
Overall I found the Garmin 740s very easy to operate and use. Rarely was it necessary to reference the owner’s manual for guidance.
Charts
The Garmin 740s chart page can be displayed as a traditional 2D vector chart, or in perspective 3D mode, or as a fishing chart—each has a specific purpose. I prefer the traditional chart view for navigation and the fishing chart when extra deep water contour lines are desired. Perspective 3D does have an interesting look but doesn’t display the level of detail found in the navigation chart view.
With a Garmin BlueChart g2 Visions card installed the unit will also display options for Mariner’s Eye 3D and Fish Eye 3D chart views.
Waypoints
To create a waypoint at present position you’d hit the Mark button. The unit then shows you the saved waypoint data and options to edit, delete, or select as MOB. If you do nothing on this menu page the unit will revert back to the chart page view in five seconds. To place w waypoint elsewhere you simply touch the screen where you want the point, the unit will zoom to the area, and popup an option list to navigate to, create a waypoint, measure distance, or show area information. A data box onscreen will show position data, bearing, and distance to the point.
You navigate to a waypoint by touch it on a chart page or by selecting it from the waypoint list. Next you’d follow through a couple menu selections and execute. If you’ve have navigation data boxes set to automatic this will bring them onscreen loaded with information. You’ll also see a course line based to follow displayed onscreen.
The Garmin 740s can store up to 3000 waypoints and 100 routes. Waypoints are identified with a user-defined name up to 10 characters in length and one of 70 symbols. You can also add a comment about each point.
Routes
We found the easiest way to build a route was go directly to the chart page, touch the final destination, build a waypoint there, and then select Route To. Once you do this you can simply add turns as needed by touching the screen and pressing Add Turn.
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When you execute and follow a route extra information will display onscreen and show navigation data to the next waypoint and the final destination. This Garmin chartplotter can go navigate a route forward, backward, on an offset, or by skipping a particular waypoint. Up to 100 routes with as many as 250 waypoints can be stored.
Tide, current, and celestial data is found via the Information page. This is the graphic tide display.
Odds and Ends
The easiest way to execute the man overboard function on the Garmin 740s is press Home, then Man Overboard, then Yes to the question—Do you want to navigate to this MOB? When you do all this the unit executes the MOB as a waypoint and displays a plethora of navigational data back to the point. The Garmin MOB function would be better if it were activated with a single button push.
Screen redraws on the 740s are fast, smooth, and fairly seamless under most circumstances.
The 740s chart page can be orientated to North Up, Course Up, and Heading Up. At sea it responded well in all settings.
This Garmin chartplotter fishfinder has an easy to use distance and course measuring tool that can be found by simply placing the cursor and then hitting Select.
The Garmin 740s is rated waterproof to IPX7 standards, which means it could be submerged to a depth of 1-meter for up to 30 minutes and survive undamaged. The unit carries a 1-year warranty.
Fishfinder
This Garmin is capable of producing up to 1000 watts of output power from its integral sonar. For my testing, I used a 50/200 kHz transom mount transducer. This transducer limits the sounder output to 500 watts. To get the full 1000 watts of output power requires a transducer with a 1kW power rating. In the depths I tested the reduced power had little to no effect on the results.
After choosing Sonar from the Home page menu, you can select how you would like to display the sounder data. Options include full screen sonar, split frequency, or split zoom. You can also choose a number of sounder setup options like A-scope, scroll speed, whiteline, color scheme, and surface noise.
In this partial screen shot you can see the 740s clearly painted all three test targets. The plus/minus keys on the top line instantly change the depth range as desired.
During our testing the Garmin 740s sonar marked all three of our submerged test targets best after I spent some time fine tuning the gain individually for each frequencies.
Once you’re on a sonar display page you see a menu field onscreen. From here it is easy to change the gain, depth, frequency, and zoom options as needed. For the latter you can choose none, 2x, 4x, manual, or bottom lock. Manual zoom puts adjustments to the size of the zoom area and the coverage zone within easy reach.
While using the sonar the plus/minus buttons can be used to manually quick change the depth setting if desired or reselect automatic depth ranging.
In my opinion the 740s fishfinder has tons of features, was very intuitive and easy to operate, and worked well presenting bottom, fish and test targets during our review.
I rated the Garmin 740s sounder good for presentation and excellent for ease of use.
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Final Thoughts
Sharp screen details, a powerful processor that makes both 2D and 3D presentations look good and move smoothly, and excellent ease of use ratings for both the plotter and sonar combine to make this Garmin chartplotter fishfinder an excellent buy.
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