Location and obstacles
Height and obstacles affect VHF reception. The best location depends on the mast, other antennas, interference and maintenance access; there is no universal position.
Cable and connections
Cable length, connectors and cable type introduce loss. Choose compatible components, protect connections from water and avoid damaging bends or runs.
Sharing an antenna
A receiver does not transmit. If sharing an antenna with a radio or transponder, use only a splitter appropriate for the equipment and follow its instructions. Not every target will be visible.
Before sharing an antenna
Check whether equipment only receives or also transmits, and consult the specifications of the radio, AIS and splitter. Do not assume a receive-only splitter is suitable for transmitting equipment. This decision affects both wiring and equipment safety.
If coverage seems poor
First inspect power, connectors, moisture and cable continuity according to the manual. Compare reception with the same electrical equipment on and off; some LED lights can interfere with VHF. Plan suitable access and assistance for mast work.