Thank you. A wealth of info. I did not realize the Datamarine would
even work as an in-hull as the DMI guy did not mention it. Tell you
the truth, if it did work, I would consider it as I do like the
current display. Perhaps I will call him again.
I have a panel-mount head and in-hull transducer combo home
from West Marine, but I think I will return it as I really don't like
the panel mount feature all that much ($129 though for the whole
unit!)
I would propose to place the new transducer near the site of the
old one, which is just forward of the engine in this stern drive
Grady White 22' Seafarer. I am told the Grady would probably be
a good boat for an in-hull as there would likely be no bubbles,
cavities or foam, at least at that point.
The "continuous wave" article surely describes my transducer
and mount to a "T." It certainly tells a cautionary tale and I now
doubt I really would want to get into all those issues!!!
I will look harder at fishfinders and you are right- for about
the same price as the DMI transducer I can get a very nice fishfinder.
(Humminbird or Garmin.) I just want to make sure I get fractional
depth readout.
Again many thanks for your continuning interest!
Frank


On Mon, 17 Jul 2006 21:44:45 -0400, "GBM"
wrote:


"frank1492" wrote
Because the boat will have to be pulled ($150) in order to remove
the transducer (from the bottom), which would make total of $300, I am
looking at other options. Most obvious is to buy a new complete unit,
display and transducer. I'd like your opinion on a couple of points,
however, before I go that route.
(1) Some of these have "in-hull" transducers which are simply
epoxyed to the inside the hull. If these are accurate, they sound
appealing. Your thoughts?

Frank - These work fine, so long as you can find a good spot to mount them -
A "good spot", is one that is relatively flat, has no core material (i.e. is
solid fibreglass) and is clear of external items that could give a false
echo (keel, prop shaft etc). You can install any transducer this way, but
the more powerful ones work better. They can be epoxied in or can be
installed in a "water" box - usually a piece of ABS pipe epoxied to the hull
containing a small amount of a suitable fluid (Castor Oil works well - water
evaporates). One way to find a "good spot" is to put the transducer in a
Zipock bag full of water and then move it around until you get a good
reading. You could even buy the Datamarine transducer and install it this
way until you get a chance to haul out, but a complete new unit may be a
better bet.

Thes links provide more detail:

http://www.tomneale.com/tips13.html
http://www.tacktick.com/products/use...pthAdaptor.pdf

and to show you are not alone:

http://continuouswave.com/maintenance-logs/newDS/

Regarding a fish finder - By all means - some of them are quite reasonable
and they provide a lot more information that a basic sounder. Perhaps going
this way would not cost much more than the DMI transducer?
I have used them, but never owned one, but if you buy from a reputable
company you should be fine - check reviews on google.

If you want to go really cheap , you can buy small dash mounted sounders for
a reasonable price and I believe they work quite well:

http://makeashorterlink.com/?J10325C6D

What would be interesting, is if the 200Mz transducer that comes with these
units would work with your Datamarine head?

Have Fun!

GBM