frank1492 wrote:
I have it mounted at least a foot off the centerline of the hull. The
hull has a deadrise of 20 degrees. While I thought there would be
plenty of good water there, at high speed there could be some
turbulence I suppose. I did it that way to avoid having the
base sit in the bilge as I was having some trouble with the
silicon adhesive the manufacturer suggested. I do always
have the option of moving it closer to the keel if I can't
live with it.
Frank



On Wed, 02 Aug 2006 08:02:16 -0700, RW Salnick
wrote:

frank1492 wrote:
I tried using the silicone adhesive again and this time got a good
bond. (Bonding the base of an in-hull Airmar transducer to the
hull.) Filled with mineral oil (calling this the "medium") as per
instructions.
Here is what is happening. At low speeds, readings are good,
no misses, but at high speed, I get quite a few false readings, both
too high and too low. Is this a problem with in-hull vs thru-hull (I
seemed to get fewer false readings at high speed with the old
Datamarine transducer) OR is it related to bubbles in the medium or
improper contact between the transducer and the medium? I see
a lot written here about good choices for the medium (marmalade?)
Some ideas here would be most appreciated as usual.
Thanks to all for your past help. Looks like we're coming to the
end.
Frank


Probably not bubbles in the medium, but rather bubbles in the water
under the hull...

bob

The whole purpose of the marmalade is to find the ideal position in the hull
to mount the transducer, not to use it as a permanent medium once you find
that position. You can then have great fun going around the boat licking up
the marmalade, have epoxied your transducer housing in the perfect location.

Dennis.