In article . com,
"feetwet" wrote:

My boat came with a Navman 4380 color fishfinder.. I have had really
poor results with this fishfinder working when I'm on plane. I was
hoping it would work at least for a low planing speed like 20-25 mph,
but the screen just goes white. I have tried tilting the transducer
forward a little, but it still exhibits this performance. The transom
mount transducer was installed by the dealer, and looks to be properly
located.

I'm scratching my head wondering if this behavior is related to the
mounting position.. or if Navman's are just sucky fish finders?

It's nice to see the SmartCraft gauges linked to my Merc Optimax... but
I'm getting frustrated with this thing.

Does anyone have any experience with Navman fishfinders?

Pics of mounting:
http://aycu34.webshots.com/image/279...6884250_rs.jpg
http://aycu17.webshots.com/image/113...8036262_rs.jpg


What is happening to you is your trying to beat the "Laws of Physics"
and those laws are not subject to political change. The faster you
go the more air, (bubbles) crosses the Transducer face, and the less
of the ultrasonic signal generated by the Transduser Crystal is coupled
into the water, and the less return signal is coupled back from the water
to the Transducer Crystal. You can either, SLOW DOWN, or stick the
Transducer down in clear water. (deeper by a foot or two) Should you
try the later, just remember that it is down there and anything you run
over is going to break it off. Must be a Weekend Skipper........

Me