Make sure your Xmit stitch/button is on high. The Antenna is tuned for the middle of the Marine VHF band and as you go further away from that (especially in low power) your signal will taper off because of higher SWR (Standing Wave Ratio). The high SWR readings will limit your transmit ability but not your receive.
Plus it is good to check all points that are accessible to the salt air. Clean all wires or plugs as a slight amount of corrosion will act like a resistor and not give you full power. For instance when you key your ptt and it transmits the corrosion will act like it is only putting out 5 or less watts. Not good for the transceiver.
One good thing to clean your connections is a good brass brush and a piece of an old brown paper bag. It cleans and polishes at the same time.
Hope this helps.
Paul
