Need more details.
1. When you push the mic button, does the radio give any sign that it is transmitting? (TX LED on, meter indication, etc.)2. If the radio appears to be transmitting, can you listen on another radio nearby to monitor yourself? (perhaps using a handheld).3. If you transmit and hear a carrier with no modulation when you key the mic, you may only have a bad microphone, broken wire, or connector.4. To test the radio further, you need a dummy load to simulate the antenna, and a watt meter. If you don't have access to this equipment, perhaps you may know a local ham radio operator that will help you out.5. If you hear nothing, not even a carrier on step 3, then the problem is probably the radio itself. This would require sending it in for repair, or replacing it with a new one. New VHF radios have really gone down in price the past year or so.6. Substitution is a good way to test your antenna. Ken Palmer, S/V Liberty