Correct Garmin plotter - transducer match ?

DownYonder

Cadet
Joined
Nov 25, 2018
Messages
13
We are purchasing a new 20' bay boat powered with a Suzuki 140. I need to find the right chartplotter - transducer combo but I'm having problems finding what I think I need.

- 80% fishing in 2'-20' depths over hard bottom and lots of grass (Deadman Bay of of Steinhatchee, FL)
- 10% deep off of same area but still under 100'
- 10% fishing off of the ICW in the Swansboro, NC area

What I think I need/want is a Garmin echoMAP CHIRP 94sv w/U.S. BlueChart g2. The problem I'm having is finding a transducer sold with the unit for shallow waters. All the transducers that are bundled with the unit are (per Garmin) "All-in-one Traditional-CHIRP/SideVü/ ClearVü optimized for depth and rough conditions." I can't find a bundled transducer that is "All-in-one Traditional-CHIRP/SideVü/ ClearVü optimized for clearer image at shallow depths".

First, am I completely off-base on the plotter ......are there better units for what I'm doing.... and any suggestion on how to get the correct transducer?

Thanks
 

ajgraz

Lieutenant Commander
Joined
Mar 1, 2010
Messages
1,858
The Garmin EchoMAP x4 (54, 74, 94, etc.) plotters come bundled with coastal charts, and lower-frequency transducers better suited to deeper saltwater. The x3 (53, 73, 93) come with lake charts and higher-frequency transducers more suited to shallower, freshwater.

I faced a similar issue when kitting out my 17' CC for use in San Diego Bay and inshore kelp: how to get a shallow-use transducer (90% of my fishing 120' or less, most of that 75' or less), but ocean charts? So I got a 74SV head unit alone (no transducer bundled), and a GT-52HW-TM transducer purchased separately. Works out magnificently for those uses.

On the other hand, I find that transducer to be severely hampered at any deeper than ~150' in salt water...I really should have gotten the GT-50M-TM (or even the GT-51M-TM) for my occasional use when deeper-water rockfishing.

So yeah, if you'll never be deeper than about 120' in saltwater, the 52HW will do it. If you'll ever want to use it any deeper, go to the 50M or 51M...and one of those may come in a bundle with the ocean charts.

https://www8.garmin.com/marine/PDF/transducer_selection_guide.pdf
 
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DownYonder

Cadet
Joined
Nov 25, 2018
Messages
13
The Garmin EchoMAP x4 (54, 74, 94, etc.) plotters come bundled with coastal charts, and lower-frequency transducers better suited to deeper saltwater. The x3 (53, 73, 93) come with lake charts and higher-frequency transducers more suited to shallower, freshwater.

https://www8.garmin.com/marine/PDF/t...tion_guide.pdf

YEP! Can't find a bundle for shallow bay fishing and purchasing them separately as you did ends up adding about $100. I'm also looking at getting a x3 bundle and buying the charts separately but that appears to be way more expensive!

What do all the Big Bend, Keys, Delta and Texas fisherman do? I would think that Garmin would have figured out that a lot of us don't fish deep out of our flats/bay boats.
 
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dingbat

Supreme Mariner
Joined
Nov 20, 2001
Messages
15,414
There is no such thing as a "shallow" and "deep" water transducer per say.

Everything is a compromise one way or the other except power. The more power you can put on a target the better off you'll be. The GT 51M is a 600W transducer as opposed to the GT 52HW which is a 250W transducer.

One could argue that a wider cone angle is best for shallow water performance with conventional sonar but the 51M has the same max. cone angle and the 52HW. Guessing they shorted the 52HW an element and are playing games with the signal processing given the price discrepancy between the two units.

Cone angles go out the window with down and side scanning sonar. Your going to see X feet of coverage off to each side of the boat relative to the depth of the water.

What you do have is the option to select a "high" or low" frequency side scan transducers. You have a choice of 260/455 kHz or 455/800 kHz.

A 455/800kHz transducer will be "clearer" but you'll be highly susceptible to imagine stability issues in open water. 455/800 kHz is pretty darn near useless on anything but the flattest of days.

The 260 kHz (stabilizing function) works pretty well even in the slop of open waters.

Bear in mind, Side Scan and DownVeiw/Clearview is pretty useless over 40' in depth.

80% spent in open water (Chesapeake Bay and the surrounding waters) between 20 - 150 feet.
15% in the open waters (Atlantic) 150 - 800 ft.
5% in sheltered waters under 20 ft.

I'm running a GT51M-TM on a EchoMap CHIRP 94SV
 

DownYonder

Cadet
Joined
Nov 25, 2018
Messages
13
dingbat....thank you for the thorough explanation!!! What you say makes perfect sense but in conflicts with what Garmin "advertises". No, I do not trust advertising/marketing and that is why I'm here asking the question.

I see where the GT50 chirp is 300W and the GT51 is 600W . Both transducers list the ClearVu/SideVu at 500W. So, if I'm fishing in 3'-10', if I understand you correctly, the additional strength of the 600W will serve me just as well?

Thanks for the help!!
 

dingbat

Supreme Mariner
Joined
Nov 20, 2001
Messages
15,414
dingbat....thank you for the thorough explanation!!! What you say makes perfect sense but in conflicts with what Garmin "advertises". No, I do not trust advertising/marketing and that is why I'm here asking the question.

I see where the GT50 chirp is 300W and the GT51 is 600W . Both transducers list the ClearVu/SideVu at 500W. So, if I'm fishing in 3'-10', if I understand you correctly, the additional strength of the 600W will serve me just as well?

Thanks for the help!!
Keep in mind that the viewing area in 5 ft. of water is less than 24". The viewing area in 10 ft. is roughly 42".

The extra strength of the GT51 will not hurt you in shallow water applications, but the 300W limitation of the GT50 will limit performance in deeper water. You'll also loose the image stability of 260kHz side scan with the GT50

The pictures of down view and side scan look great when taken 12" from the screen then blown up to fill a 21" display on your computer. You get an entirety different perspective viewing the tiny little white splotches on a 9" display from 3 to 4 feet away.

The GT51M is a better transducer for deeper waters and locations where the water tends to be rougher.

The GT50M would be good if you don't fish deeper water and the water is more often than not smooth.
 
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DownYonder

Cadet
Joined
Nov 25, 2018
Messages
13
The more I thought about the FF actual application, I realized that I would never use it in the shallows. We fish the creek entrances and banks around high tide or holes during low tide. The only time it will really help is when we go outside (which will probably be more now that we have a larger boat) and as a depth sounder.

I ordered a Garmin EchoMap Plus 94sv with the CV51 AND I found one on sale for $150 off. I'm sure that I will be pleased.

Thanks again for the help!!
 

Kerch

Recruit
Joined
Dec 3, 2018
Messages
1
I have a Yamaha F100 seems retifier went bad and fried Cdi . Does anybody know the upgraded part number
 

NYBo

Admiral
Joined
Oct 23, 2008
Messages
7,107
I have a Yamaha F100 seems retifier went bad and fried Cdi . Does anybody know the upgraded part number

Welcome to iBoats! :welcome:
You posted to a thread totally unrelated to your issue. Start your own thread. You may also want to search for the part in the shopping section.
 
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