Robert Miller of Port Isabelle, Texas, asks:
“If I don’t bother to clean my radome when it gets covered with dried salt spray, dirt and dust, will that have any effect on the efficiency of my marine radar antenna?”
Gordon West replies:
It could be significant, which is why you should always keep your radome as clean as possible. Soot, dust, and salt are conductive contaminants that affect the radar’s weak signal reception. These contaminants won’t affect signals leaving the antenna but they will degrade any very weak return echoes enough that they don’t show up on your radar screen.
For example, if the radome is not clean, a fishing float that is directly ahead of you might not show up on your screen even when it is 500 yards away. If the radome is clean the float should show up clearly at that range. Use a mild soap to clean a fiberglass radome. Before you start cleaning be sure the radar is off, the circuits are disabled and the system is marked so that no one accidentally turns on the radar while you are cleaning the radome. Once it is clean, rinse it with freshwater and then dry it with a towel. Although waxing a radome will make it shine brightly, it won’t have any effect on the radar’s performance.