Thanks Art,once I get it hooked to a battery I will use simulator mode and have it check itself out.
Oldschool I've heard inside and/or epoxied under the boat. Mine being portable came with a suction cup I quickly got rid of. Made a stainless shaft,stainless clamp,completely universal but always in the water. I will try to keep it in a small bucket of water while I'm testing it.
Sinker,worse comes to worse,I guess a new transponder may be needed. Thanks.