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Garmin 840xs transducer help

Old 02-24-2015, 07:44 AM
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Default Garmin 840xs transducer help

Ok, I am ready to pull the trigger on a Garmin 840xs I am confident this is the machine for me however, transducers are foreign to me and seem to get more confusing the more I read. I will be installing this machine on a 22' Cape Horn bay series and due to finances I have been looking into the xducer that comes with the machine for the extra $100. There is little information on the paired xducer from Garmin I believe it is a transom mounted xducer? The vessel has trim tabs installed and there is 19" from the edge of trim tab to jack plate will this hinder the ability of the xducer or should I have room to install a transom mounted xducer? there is also a underwater light mounted nearly dead center between the tab and jack plate that extends out possibly 3/4" ?

Later this year I will be installing the GCV 10 for side vu capabilities and changing from the original transom mounted xducer to a thru-hull xducer for higher speed and CHIRP readings when fishing in the gulf. I'm sure I'll be back for more xducer advice then.

I also have a clear picture on my PC of the area of the vessel I intend to install the xducer, but being technologically challenged I cant figure out how to get it on the thread.
Old 02-24-2015, 08:26 AM
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This is the transducer that will ship if you buy the 840xs / 1040xs combo unit.

Garmin GT20-TM – Transom Mount DownVü 500 W (CHIRP 455/800 kHz) Traditional 500 W (77/200 kHz) Transducer with Temp (8-pin)
This 20 ft transducer cable with built-in fast response temperature sensor has a power rating of 500 W; a depth of 1,900 ft (traditional) and 750 ft (DownVü); an operating frequency of 77/200 kHz (traditional) and 455 (DownVü); and a 0 to 70 transom angle.
Part Number: 010-12087-01


How deep are you fishing?

Another option is the GT21-Tm..this will give better depth capabilty than the GT20.

Garmin GT21-TM – Transom Mount DownVü 500 W (CHIRP 260/455 kHz) Traditional 600 W (50/200 kHz) Transducer with Temp (8-pin)The CHIRP DownVü element has a power rating of 500 W and operating frequencies of 260/455 kHz. The traditional sonar has a power rating of 600 W and operating frequencies of 50/200 kHz. It also includes a built-in fast response temperature sensor.

Last edited by semperfifishing; 02-24-2015 at 08:52 AM.

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