 GPS / VHF NMEA parallel wiring - '06 Edgewater 265EX
Hey guys,
I've got a Raystar 125 GPS Antenna and an iCom VHF IC-M422 radio. I've decided to move my vhf radio from my helm to my overhead electronics box to make room for a Garmin radar display on the helm. Currently, I've got my gps antenna and my SimRad AC10 connected to my raymarine c120 mfd via an nmea 0183 distribution block behind my helm. Since both the gps antenna and the iCom radio are now mounted overhead and there is very limited space in the cable run from my overhead electronics box to my helm, I'd like to have only one nmea cable run down to my helm distribution block from the overhead box.
What I was thinking of doing was cutting the nmea signal cable that already runs to the helm, connecting it to another distribution block in the overhead box, and wiring both the GPS antenna and the VHF radio to it. Should this work? It's supposed to work so that the VHF radio nmea "in" needs a position from the gps antenna, and the "out" sends positions of other distress calls to the c120.
I'm also installing a Raymarine ST40 BiData display (basically as a repeater) in the overhead electronics box which has to be connected via sea talk to the c120. It's possible I could connect the gps antenna and the st40 to the c120 via sea talk using a 3-way junction box. If i did that, I could use the existing nmea cable to go from the vhf to the helm dist. block. However, in that configuration, would the gps position data be output over nmea by the c120 and available to the vhf radio? Also, is it a huge draw back that the c120 would have to be on for the vhf to have position data?
Clearly, I only "sort of" know what I'm doing here and boating season in NJ is quickly approaching, so any help would be greatly appreciated.
Thanks
Ben | 
