Best Transducer for fishing-Garmin Sounder

[pescador]

My transducer (P66) bracket broke late in the season due to hitting a chunk of wood as I rounded Race Rocks early Sept. I had to hold it on with nylon zap straps the last couple of trips. I am seriously considering replacing it and going thru/in hull to get the improved performance/image quality. I run the Garmin 740S with the P66 mounted off my transom right now. It is ok, but, I suspect I can improve the view with a better quality transducer. My primary focus is fishing and typically I'm in 30-200 ft of water. That’s what I'd like to target it terms of improving the view. Anyone out there changed transducers on a Garmin sounder? Are there any high performance transom mounted tranducers in the market. I see Airmar makes a few (http://www.airmartechnology.com/2009/products/marine-product.asp?prodid=260&manf=All) but, will they work for fishing? What did you install, how and was it worth it. I’m not real keen on drilling a hole in the bottom of my boat, but, will entertain the idea is there is a material improvement.

 

[wildthing]

p79 is in hull is going to be the same as your p66
for your money the p66 is prob going to be the one to stay with
as if you go in hull your going to lose some detail
and jumping up to a m260 or 1k trannies may be a letdown
as the sounder you have may not have enough to power them proper
more or less in the same boat as yourself
unless you upgrade the whole system to a 1kw or chirp system

 

[Hookin'up]

Pescador, you have options, but you can also just glue a P66 down to the floor in a good clean area and get a reasonably decent picture still,
I think your in a Grady correct? if so look for the flat spot in the bilge area right at center beam, that is there for just that and should present a clear picture
it should be an area about 6"x8" its a cheap try if nothing else, Ive broke off a couple of those p66's now on the old garmin system they don't hold up all that well.
keep in mind with any shoot thru the Grady hull pushes the limits of them with the bottom glass being nearly 1.25" thick, a Thru hull would be ideal but as wildthing has already stated make sure you have the power to drive one.

 

[Charlie]

My transducer (P66) bracket broke late in the season due to hitting a chunk of wood as I rounded Race Rocks early Sept. I had to hold it on with nylon zap straps the last couple of trips. I am seriously considering replacing it and going thru/in hull to get the improved performance/image quality. I run the Garmin 740S with the P66 mounted off my transom right now. It is ok, but, I suspect I can improve the view with a better quality transducer. My primary focus is fishing and typically I'm in 30-200 ft of water. That’s what I'd like to target it terms of improving the view. Anyone out there changed transducers on a Garmin sounder? Are there any high performance transom mounted tranducers in the market. I see Airmar makes a few (http://www.airmartechnology.com/2009/products/marine-product.asp?prodid=260&manf=All) but, will they work for fishing? What did you install, how and was it worth it. I’m not real keen on drilling a hole in the bottom of my boat, but, will entertain the idea is there is a material improvement.

The link goes to the 'TM260 —Transom, 1 kW.' The 1kW certainly will improve the view for both fish targets and terrain and if that's the one you want - go for it. The 740s is rated to power it. I quote:

"If you want to add underwater digital sonar scanning capability, Garmin also offers the GPSMAP 720s and 740s combo models — which feature a built-in 1-kilowatt capable sonar transceiver that can clearly define fish targets and terrain features as far down as 2,000 feet (with a dual frequency transducer) to keep you apprised of what’s happening below the waves."
http://www8.garmin.com/buzz/gpsmap700/

If you want some other choices that will also work - Take your pick:
http://www8.garmin.com/transducers/d/transducer-selection-guide-2015.pdf

It really is a personal preference, but I would highly recommend going to 1kW!

 

[pescador]

Thanks gents. I am leaning towards the TM260 Transom mount 6 PIN version. I see that Garmin says it is compatible with the 740S. My only question is that will a beamwidth of 19 to 6 degrees be ideal for BC fishing? I don't want to end up with a beamwidth intended for off shore Marlin fishing or some other species. The P66 according to Airmars website is: 50 kHz—45° and 200 kHz—11°. That sure looks dramatically different to the TM 260 Beamwidth. The P66 covers a broad diameter at depth, which in principal seems to be a better way to see whats below the boat. I get one change here to make the right decision. Pros cons please....

Also, the data on Airmar's websites states the following related to benchmarking the P66 against the TM 260:

Model Power Rating Performance Increase
P66 600 W Good Benchmark model for comparison
TM258 1 KW Better 25 times more sensitive at 50 kHz 16 times more sensitive at 200 kHz
TM260 1 KW Superb 50 times more sensitive at 50 kHz 13 times more sensitive at 200 kHz

Looks like the performance should improve exponentially.

 

[trophywife]

happy with my p66

 

[Derby]

Love mine too.. I use it on my back HD-7....

 

[Hookin'up]

Pescador,
I spent the money and went with the m260, In hindsight for a few dollars more I should have done the ss264w pairs
but you will be drilling hockey puck sized holes through the bottom
I use the m260 on split screen with one side on 50khz and the other on 200khz, that way I can see whats in the general area on one the side(25* cone) and then whats directly under the boat on the other (6* cone angle) theres really no spread on that baby,
these 260's are massive and I have heard tell that the TM260 can and will affect the the boats performance, thats why I went in hull.
best guy to call for advice on Ducers is Mike at Harbor Chandler, I also got the best price from him too

 

[Hookin'up]

Love mine too.. I use it on my back HD-7....

are you not running a P79 in hull?

 

[pescador]

I''ll call Harbour Chandler. I know they are very big, it weights 8 lbs. Thanks again for input gents...

 

[Derby]

are you not running a P79 in hull?

Yes thought it was the other one.. It works great on the back end of the boat...

 

[Sir Reel]

This is a pretty good article about transducers. Types and installation methods.

https://www.furunousa.com/Learning Center Documents/FurunoTransducerGuide-LR.pdf

 

[Sr SQ]

Thanks gents. I am leaning towards the TM260 Transom mount 6 PIN version. I see that Garmin says it is compatible with the 740S. My only question is that will a beamwidth of 19 to 6 degrees be ideal for BC fishing? I don't want to end up with a beamwidth intended for off shore Marlin fishing or some other species. The P66 according to Airmars website is: 50 kHz—45° and 200 kHz—11°. That sure looks dramatically different to the TM 260 Beamwidth. The P66 covers a broad diameter at depth, which in principal seems to be a better way to see whats below the boat. I get one change here to make the right decision. Pros cons please....

Also, the data on Airmar's websites states the following related to benchmarking the P66 against the TM 260:

Model Power Rating Performance Increase
P66 600 W Good Benchmark model for comparison
TM258 1 KW Better 25 times more sensitive at 50 kHz 16 times more sensitive at 200 kHz
TM260 1 KW Superb 50 times more sensitive at 50 kHz 13 times more sensitive at 200 kHz

Looks like the performance should improve exponentially.

I have done this route with the 260 then moved on to the 270W.
I can tell you from first hand experience there is no comparison for the type of fishing we do……
The 260 is a great ducer but is not really designed for the shallow water trolling we do, it excels in deep water or if you drift fish with your gear right under the boat.
I found its beam is too narrow…………..at 100' on 200hz its showing you an 11' circle where as the 270 shows a 45' circle at 100'
Look into the TM270w or the M270w if you want a shoot thru you will be happier