In tests, we have seen this action take place in as little as 30 minutes. The splice connectors may then need to be replaced. If you must splice, use coax-seal or Liquid Tape to seal against water entry. We have both in stock. The two frequency bands are quite different and require different types of circuits and transistors for optimum performance.
Competitive systems use a single amplifier to cut costs though they also cut performance.
Using separate amplifiers also reduces the chance of interference on one band, spilling over to the other. A. Naval antenna radomes are made of thick high impact ABS plastic with Korad UV inhibitors which will protect the antenna from yellowing and plastic degradation for many years. Thousands of Naval brand antennas have been in continuous service in excess of 10 years without any sign of sun damage. The foam also acts as a moisture barrier. Naval antennas are common the world over on tugs and workboats where engine vibration is quite severe and constant 24 hours a day in many cases.