Agree, but in this case it's all my fault. I knew better, but did not follow my own procedures, so I deserve it. Not if you are in a 'dog and cat fight' for the rare one. It was not a single cycle at maximum power. The power supply fan switched on for the first time. I did not know it even had a fan. It may not be the PA itself, but the temperature control. The radio switches off when it goes into TX, then it switches on again after a few seconds. The radio is close to 20 years old, bought used. I got my money's worth. Again, coincidence, maybe.