Are you sure that the TV station didn't go off the air?
Back in the mid sixties, the Northeast had a massive power blackout, taking out New York City and its TV stations. I was in Bergen County NJ and our power company PSE&G was the only one in the region that didn't go down. The person in charge of the power plants that time didn't like what the meters were telling him, and he dropped all connections to other power companies. We had lights, but no TV reception because all the stations were dead. Heard that some people ran out to buy new TV tuner tubes because they thought that was the problem...
Oddly enough, again we didn't lose power 2 years ago when we had that big blackout in Ohio and the Northeast. Though most of our region did. Maybe because the guy who was in charge of the power plant lives a few houses down from here
The powerline voltage did oscillate wildly from 90V to 140V every half minute for an hour. Who knows what the powerline frequency did...