Hi Giles.. If you can remove the antenna of your hand held radio, there's a good chance that you can get an adapter from Radio Shack..or the mfr. that will permit an external antenna.
I don't have one for my HH marine radio, but I do have one for a HH CB unit that works great. Harvey/ Ga M-17 Stargazer #294 _______________________________________________ http://mailman.xmission.com/cgi-bin/mailman/listinfo/montgomery_boats
