Here's one thread you might find some interest in. There are pics and explanations of fish finders working on the water. Both while moving and while anchored. There are some interesting pictures from some of the economy model finders all the way to some of the most expensive models.
http://www.crappie.com/gr8vb3/showthread.php?t=21721
Another suggestion is to visit the Lowrance website and download the product manual.
http://www.lowrance.com/OEM/Products/X37TX.asp
Also read starting here to help under stand sonar and how it works.
http://www.lowrance.com/tutorials/so...utorial_01.asp
Hope this helps some.
Health nuts are going to feel stupid someday, lying in hospitals dying of nothing.