Depth sounder transducer location?

[Joesaila]

I am miffed as to why my transducer is so far back on the bottom. I took a walk through the boat yard and noticed most other boats had the same location. One boat did have the transducer forward which seems to make more sense. I want to know what I'm approaching and not what I'm on...Does that make sense? Your feedback will definetely help me out. I'm thinking of placing it where the 'speed wheel' is located forward, as that seldom functions and w gps I don't think its practical anymore. Thanks!

[sailingdog]

It may have to do with turbulence under the hull. The depth transducers don't shoot well through aerated water...

[dbruce85]

The one I just purchased suggests, forward of the keel, just off center.

[Idiens]

Most depth sounders are averaging measurements to give a smooth output value, so even with the transducer on the bow, the measurement on the dial is valid for the stern when underway. If you want to look forward, get a forward looking sonar. Google Echopilot, for example. Otherwise deeper is better, to keep the transducer in the water and as far as possible away from wake and prop induced bubbles (in reverse).

[Northeaster]

In my boat, there is a floor liner (floor pan), that extends up into the V-berth. You would have to cut a hole in this floor pan 1st, to then have access to the real hull. May be something like that, that made them choose further back?

[SEMIJim]

Originally Posted by Joesaila

I am miffed as to why my transducer is so far back on the bottom. I took a walk through the boat yard and noticed most other boats had the same location. One boat did have the transducer forward which seems to make more sense.

Depth and sonar transducers need to stay in the water (or, if an in-hull transducer, at least below the water line) and away from interference from turbulence, mechanical and electrical interference and obstructions such as the keel. Most recommendations I've seen are "a few feet forward of the keel, as close to the center-line as practical."

Originally Posted by Joesaila

I want to know what I'm approaching and not what I'm on...Does that make sense?

It makes sense, but it's a futile quest. (Unless you're willing to invest in a forward-looking sonar.) Consider: Have you ever tried to stop your boat quickly? Even at realatively low speeds (3 kts under motor, say), sailboats just don't stop very fast. Several tons of mass, tiny little motor, tiny little prop. Having a depth or downward-looking sonar transducer another 10-20' forward just isn't going to make much of a difference.

Originally Posted by Joesaila

Your feedback will definetely help me out. I'm thinking of placing it where the 'speed wheel' is located forward, as that seldom functions and w gps I don't think its practical anymore. Thanks!

Why does it seldom function? Ours gets weeds in it, from time-to-time, but it usually clears itself pretty quickly. If not: It's a trivial operation to quickly pull it, clear it, and put it back in. What that knot meter is telling you is not the same thing as what the GPS is telling you. The knot meter is telling you your speed through the water. The GPS is telling you your speed over land. I would not want to do without my knot meter any more than I'd want to do without a compass.