Originally Posted by whisper
Is there anything I can do to test my current aerial or is it a case of checking the connections?
Only reliable way of checking antenna system is using am SWR meter. This will clearly show if the cable/antenna are working efficiently. Apart from checking all the connections, including ferrule or whatever in antenna base, and retesting, there's not much else you can do. Be wary of continuity/resistance tests as even antennas from the same manufacturer can have different characteristics.
You might find a local radio shop or repair centre will let you borrow a meter. They have to be suitable for the VHF frequency range (ie cover 150-200MHz) to work correctly. Don't use a CB radio one for example. You can do it anywhere - no need to be near the sea as you aren't relying on any message actually being received/transmitted.