Ron, we don't have a transponder, just a SR-162 Smart Radio 2-channel receiver and antenna splitter. The antenna is an old Shakespeare 5225XT 6db, the top of which is at 33 feet. It's shared with one of our two VHFs. We think AIS is great, but don't see the need for us to have a transponder. Our experience is that invariably, ships with sea room always see us and (so far!) alter course at least 10 miles away to provide a minimum of a 1 mile CPA. Of course we are carrying all that aluminum top-hamper! We do see a use for transponders for "conventional" FRP trawlers, though, as despite having a modern 6kw Furuno, we are "surprised" by many and always wonder why they don't at least fit a reflector on the mast. Best, John >John, I forgot, what AIS setup did you get? ************************************** See what's free at http://www.aol.com.