Transducer and SONAR Options for 13-foot Skiff

Electrical and electronic topics for small boats
NorthShoreWhaler
Posts: 21
Joined: Sat Oct 19, 2019 7:51 pm

Transducer and SONAR Options for 13-foot Skiff

Postby NorthShoreWhaler » Sun Oct 20, 2019 9:01 am

I just bought a 2006 Boston Whaler 130 Sport. It is a second boat for me, the larger one is a 30' Grady walk around. The 13-foot boat's primary use will be cruising tidal rivers and inshore striper fishing.

I need some ideas on where to mount a small SONAR as well as the SONAR transducer. A suggestion on SONAR models would be helpful as well.

[Rather than just a SONAR, a multi-function display with] with a Global Positioning System [receiver, a chart plotter, and electronic charts] map would be great. I like to mark routes into shallow area

I may keep this boat in a slip. Making holes below the waterline is less ideal.

Jefecinco
Posts: 1592
Joined: Fri Oct 09, 2015 6:35 pm
Location: Gulf Shores, AL

Re:Transducer and SONAR Options for 13-foot Skiff

Postby Jefecinco » Sun Oct 20, 2019 10:13 am

Holes below the waterline are unavoidable unless you use a mounting such as a Stern Saver for mounting the transducer. The Stern Saver is available from eBay for approximately $50.00. Otherwise careful sealing of the mounting screws with a waterproof caulk should eliminate any concerns over leakage.

I mounted a Raymarine Dragonfly 4 on our 1981 Sport 13. I used a RAM mount due to the lack of space at the boat's helm and for the flexibility the RAM mount provides.

I mounted the transducer on the starboard side of the transom using a home-made stern saver made from KING StarBoard. Due to the curvature of the transom I mounted my 3/4-inch-thick stern saver with screws. I used a stern saver so I could adjust or change the transducer without drilling additional holes in the transom.

I routed the transducer cable through the engine well drain to avoid a drilling a large hole in the transducer. I've heard some criticism for routing the cable through the drain but it has worked well for the past few years and the engine well continues to drain quickly.

The Dragonfly is a good fit on the 13-footer. A 5-inch-screen or larger, also available in the Dragonfly Series, would be easier to read and fit about as well with the RAM mount. The transducer is shockingly long but highly effective. The Dragonfly uses Navionics mapping cards which I have found to be highly accurate. Customer service has been outstanding.
Butch

NorthShoreWhaler
Posts: 21
Joined: Sat Oct 19, 2019 7:51 pm

Re: 130 Sport: Transducer and fish finder options

Postby NorthShoreWhaler » Mon Oct 21, 2019 8:19 am

Thanks for the recommendation of the DRAGONFLY. I’ll take a look into the DRAGONFLY. I have a Raymarine device on the big boat, so I’m familiar with them.

jimh
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Location: Michigan, Lower Peninsula
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Re: Transducer and SONAR Options for 13-foot Skiff

Postby jimh » Mon Oct 21, 2019 7:35 pm

What is your budget for a combination SONAR, GNSS receiver, chart plotter, and included electronic charts? Without knowing some money limit, it is hard to make a recommendation for a particular device. These things can easily range in price from $300 to $3,000. The principal determinant of price is the size of the display screen, and if the display is a color display.

There is nothing I can think of about the transom of a Boston Whaler boat that would require special consideration when installing a SONAR transducer. Follow the manufacturer's instructions for location and orientation. Boston Whaler boat transoms are reinforced with plywood. The plywood will easily hold a self-tapping screw. Use of sealant is essential.

There are a million SONAR transducers attached to the transom of small boats with self-tapping screws and proper sealant. I don't see anything unusual about your boat or its transom what will need special care or re-engineering. If you use a stainless steel screw fastener with a Phillips head and plenty of sealant, there should be no concern about ingress of water into the transom via the screw fastener hole.

For a 13-foot boat, you probably won't be operating in water that is extremely deep. As long as the SONAR works in the depth range you expect to be in, you don't need a CHIRP SONAR or a kiloWatt-or-more SONAR power. A simple monotone pulse SONAR should be adequate for depths to almost 1,000-feet.

If you are buying electronic charts, make sure the charts are good for your area. Generally these days the choice of electronic charts available is determined by the brand of the chart plotter. Very few chart plotters are able to use multiple types of charts. GARMIN chart plotters are particularly parochial; they only use GARMIN brand charts or charts from chart companies owned by GARMIN. Often when you choose a brand of chart plotter, you are also choosing a brand of electronic charts.

I really like NOAA charts, both printed and electronic. I think RAYMARINE is one of the few chart plotters that can use NOAA charts, although you have to get the NOAA charts from RAYMARINE for them to work with their chart plotters. NOAA electronic charts are free and cover coastal areas. They are published in standard digital chart formats. The problem with using them is that most recreational-grade chart plotters will not work with the international digital chart formats; the recreational-grade chart plotters all tend to use proprietary chart formats, which bind you to buying expensive charts, usually made by the same company that made the chart plotter.

If you are an avid angler and need the SONAR for locating fish, you probably will want to emphasize the SONAR capabilities of a multi-function display more than the electronic chart plotter and GNSS receiver.

There are several major brands such as GARMIN, NAVICO (makers of SIMRAD and LOWRANCE), RAYMARINE, and HUMMINBIRD. All of their products would be suitable. I'd stay away from off-brands like Si-Tex.

In choosing a "GPS" receiver, I recommend you look for a GNSS receiver that can use GPS, GLONASS, and GALILEO, the three global navigation satellite systems available now. A receiver that only works with the U.S. Air Force NAVSTAR Global Positioning System is a bit out of date these days, but for some reason the recreational marine chart plotter makes seem to be slow is adopting better receivers to get GLONASS and GALILEO.