Jere Lull wrote:
In article ,
"JG" wrote:


Interesting. I used a piece of PVC pipe slightly larger than the sensor. I
cut the PVC at a slight angle, so it would sit flush against the side of the
bilge, then epoxied it in place so it would hold fluid. I put the sensor on
another piece of PVC with a small groove on it and the pipe so it would stay
in the right orientation, put in the oil, then put the sensor/piece combo
in, and put a cap on (unglued). The cap keeps the mineral oil from sloshing
out.


A number of people on the Tanzer list simply caulked glued the
transducer to the hull. Doesn't have to be straight up and down, just a
good, solid connection.

I did that with my last boat and would not hesitate to do it again.
Since the newer fishfinders are pretty sensitive, the minor loss of
power doesn't affect them much. In fact, the old Apelco 260 glued
inside the hull was a bit more reliable than the newer 262 mounted
though the hull - the new one needs the sensitivity backed off at
times or it focuses on powerboat wakes more than the bottom. Still, a
FF is much better than a simple digital sounder.

Even if you plan to mount one of those fluid chambers, or drill a
hole, its worth trying it simply glued on to make sure you have a good
spot. Sometimes a sounder will unexpectedly see the keel or rudder, etc.

Some people get confused about the tilted transducer, thinking it will
give false reading due to the off-axis geometry. However, the sounder
will respond to the first returned echo, which will be the shortest
path and the true depth - not counting weird effects or fish, of
course. The problem with being tilted is that the strength is reduced
off-axis. This is not a problem at 5 degrees, but a narrow hull may
only have a mounting spot at a steep angle. Since such a hull
probably heels more, its conceivable that the sensor could be almost
horizontal on one tack - not a good thing. One should consider the
beam width of a candidate unit - they are different, and some have
multiple frequencies which have different beam widths.