LarryT wrote:

Charlie the Ziploc bag worked like a charm. We took the boat out
yesterday and hooked up the depth finder. I placed the transducer off
the back of the boat and took a reading. I then place the transducer in
the bilge and checked the reading. The reading inside was 3 inches
different than the reading I got when just placed it in the water.

Just out of curiosity, how did you determine the two readings were 3"
different?