Power radio aerial failure

I didn't realize the necessity to check the drain point on the radio aerial. (In fact, I didn't know one existed.)
A mud wasp had filled it, and rain built up in the drain tube until the water was sufficienty deep to destroy the motor.
Had to have the whole unit replaced. An un-necessary expense.
I will be checking the aerial drain every week whilst the wasps remain active at this time of year.
cheers
Ian