If the finals blow instantly or very quickly either a issue in the radio final circuit or a very very high SWR at the radio----next time if you try it--do it into a dummy load and not the antenna.
Also it would pay to double check that right parts are installed and look for shorts or opens at the output transistors.
A common mistake also made is when one final is bad--not replacing both finals--the remaining transistor has a bad junction and quickly pops the transistor that was replaced.
SD TECH
Why on earth would you use Mosfets? Yeah, there is so much RF floating around at the rear of the radio and the coax fitting it is likely popping them. The problem is they are likely very close to the unshielded coax connector and RF is getting them--yeah a Mosfet is more stable and may give higher output but what good does it do if this happens---doubt it is the coax or the A-99 unless you have high reflected RF coming back at full power.
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The SWR is perfect. The question not only pertained to having a radio to blow two sets of MOSFET finals, but the same radio did not blow the regular finals. But the main question is why do I have much more static than usual with a great ground system and everything. I was only left with the possibility of static electricity in the radio possibly being the cause. Any ideas? As a side note, the antenna (Antron 99 and coax) is approximately 20 years old now.
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