Tower light outages are fairly typical in this business and I have spent a fair amount of time at various tower bases poking around in the junction boxes looking for trouble. Over the years, I have replaced several old mechanical tower light flashers with these SSAC solid-state units. The SSAC units are nice, in that they have a zero voltage turn-on, which tends to extend the service life of incandescent bulbs.
This unit appears to have taken the brunt of a lightning strike:
I would hazard a guess that lightning struck the top part of the beacon housing where the bulb socket is located, then traveled down the AC line to this device. Luckily, it appears the wire insulation inside the conduit to the beacon fixture is still intact. Sometimes, under high stress, wire insulation can fail, as it is most often rated for 600 volts maximum. I have also seen that happen on more than one tower, especially if water has made its way into the conduit.
Side view, this was mounted on a hot AM tower, but was not the unit designed for high RF environments. Those units are denoted with an “RF” suffix. The difference between the two, the RF models have bypass capacitors installed internally.
Lightning path to ground, through the bottom of the case.