Posted by: jerrysmith on Nov-15-11 6:50 PM (EST)
Keep it simple.
On a 2 week fishing trip with an aluminum canoe, we just took electrical tape and wadded it up into a crude circle and stuck it to the bottom of the canoe. A bead of caulk would do just as well. Drip some water off the paddle and put the transducer in the puddle.
I have owned fiberglass boats in which I just placed the transducer in the bilge water. Works fine unless the hull is balsa core of some honeycombed construction.
Just last week, I glued a 4" piece of PVC to the bottom of an aluminum row boat for a Humminbird transducer.
Be aware that the built in temperature sensor will only give the temperature of the bottom of the boat.
If the temperature is important to you, you can drill a large hole in the bottom of the boat, but then you may notice other drawbacks.
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