There is a big difference between being able to receive and transmit. Your transmit capability is dependant on the height of your aerial, the height of the receiving aerial AND the Db of your aerial. ( effects transmit pattern)
High Db is good. Those stupid little 3 ft. whip aerials which are only 3Db are only good for strapping to a rubber duck in a pond. 8 ft, 6 Db. aerial is the best for a RIB in my opinion.
Of course, Codders is going to disagree as usual and come up with some super tech. explanation of the subject.