Well, the replacement GPS antenna turned up, a Raymarine 125 . Opened the box and was somewhat dumbstruck by the contents, 3 seperate installation guides, two bags of bits, one long cable and 5 other cables with various connectors , plus conversion blocks and more connectors. I guess this is what happens when a compnay uses so many protocals, plus NMEA . I was not looking forward to what should be a simple connection. Plan A, follow instructions.......fail, Plan B follow instruction in installation manual 2.......fail. Plan C , use convertors as suggested in installation manual 3....fail. Go to bed !
Get up early and cut connector of end main cable...........old school approach, connect one wire to direct power , not through SEAtalk bus. Crimp data wire from Antenna to Seatalk in , crimp shield to Sea talk. Hey presto, GPS comes on line on master display at nav station but not on slave display at helm. Shit !! Follow back helmstation seatalk to junction box. bring master connection back to same box and twist wires together into junction block. BINGO, GPS is up and running at helm and nav station. Sounds pretty simple, only troule is this all took a total of 12 hours. Had to dismantle aft cabin to follow cables back, dismantle Nav station electronics , take apart Nav pod at helm, fit antenna on dofger top instead of aft rail ( Raymarine only supply 20 feet of cable). General pull the interior apart to run cable. The photo's don't do the dishevelment any justice. A day spent drenched in sweat but one which ended in VICTORY. It would have been quicker to learn how to use a sextent !!!