I purchased & installed a Furuno 1715 radar on the boat -- unfortunately; I
can't rely on it as it gives me false targets.

I can have the gain adjusted so that it's working; then suddenly (same
conditions) it's spotting a lot of "clutter" all over the screen -- re-adjust
the gain; (it's a constant adjust, readjust) -- clutter is gone; and so is a
"known target" -- re-set the gain back; clutter is gone; target back + a new
one -- the target is right in front of me -- clear day -- calm seas -- nothing
in front of me - no logs, no birds, nothing -- then poof -- gone.

continue and suddenly I'm surrounded by a solid target (a thick ring is
displayed around me) -- but there's no other boats anywhere near me.

I've turned off gps, vhf, engine, radio, lights -- I can get similar behaviour
with just the radar running.

I sent the radome & display in - they bench tested it and said "no problems" - I
put it back in --today and ... same thing.

I'm desperate to get this going -- it's been too long to return it; and it's too
expensive for me to ditch it...

Thanks
-josh