Originally Posted by dubrus
is there a set angle range for these to work within?
Depending on the depth of the water it can be quite sensitive to changes in angle. Like when you are riding bow high and the transducer points "forward". Generally it should point straight down while underway AND while at rest. This requires a bit of fiddling and splitting the difference in practice.
Ther is about ~15degs of wiggle room on the angle, because that's how big the signal cone is. If a signal is not being returned from the bottom because its "skipping" off the bottom at an angle the unit will flash nonsense or read a very very shallow or over-range depth (I have gotten both bogus signals from my Humminbird).
The plastic bracket on the transducer has two nubs on the inside. The actual sensor is supposed to break free and swing up on impact with an object. If those nubs are worn it won't stay snapped back down though.