So entertaining to watch clueless folks out of the area solve our problems for us. Thanks guys!
No one is solving your problems, just pointing out how you got to where you are today. The big question is what are you going to do about the issues.
As MTS2000 pointed out as time goes by, the landscape changes. This changes the way any radio system performs. Before any money is spent on new radios, the malfunction of the existing system needs to be identified.
I have a major advantage over just about everyone else on the chat group here. I get to travel around the country a good deal of the time getting to talk with the users, managers and radio people using and working on the radio systems. The trend is to ignore the basics like tower maintenance, antenna systems and grounding systems. If the radio doesn't work, the first move most take is to replace it all. Great for the radio vendors, radio shops and real bad for the tax payers.
Many of the antenna systems out there on old radio systems are 10 to 15 years old and have never been touched. If your using a folded dipole antenna, the metal corrosion has about eaten the antenna to pieces. The coax cable has probably had water intrusion and the coax connectors could possibly have corrosion inside them also. This is not based on speculation, but from hands on inspection and chats with the radio and tower repair crews. Antenna systems are like an automobile in New England. They only last so long before the road salt eats them to pieces. If your near the ocean, they won't even make the ten year mark.
In the Gulf Coast area, if your metal antenna lasted more than 6 to 8 years, you were doing good. Why a metal antenna, the lightning strikes take out the fiberglass poles all the time. Which antenna works best for you? That depends on where they are installed and how much salt, wind and ice you have to put up with.
Maybe just maybe people will learn from those that have gone before you. It is faster and easier to learn the fast way than having to spend years learning the hard way. It is easier to walk in the steps of those in front of you than to cut your own virgin trail.