Yep, this was surprisingly common. When the picture tube in old B/W TVs lost emission, the EHT voltage increased to the point that it was constantly arcing and flashing over. But because the arcing was synchronised to the TV signal, it didn't cause much interference on the faulty TV set. But it did create a horrid rolling bar on any TV set nearby which was tuned to a different channel. So the old lady had no idea she was causing problems.

And there's a twist to this: ADSL data networks attempt to feed broadband signals over unshielded (and poorly balanced) phone lines, which means that they are intolerant of legitimate radio emissions from licensed services nearby.

The ADSL system attempts to compensate for conventional transmissions by dropping out those channels, but any wideband impulse causes the entire system to hang while it unsuccessfully tries to find a clear set of channels. So each pulse locks up the system for a few minutes while it renegotiates.

A variation on this is the ignition on the Postman's motor bike which wipes out all the ADSL in each street that he visits.

The bottom line of course is that ADSL was a horrible hack which attempts (and fails) to bypass the laws of physics.