DavidKaye have you had a chance to look at the signal on a spectrum analyzer?
No, and yes I am aware that FM signals are by their very nature full of spurs. That's the nature of the beast. The fact that there were never any complaints about interference mentioned in any of the FCC's previous shutdowns seems to say that Pirate Cat wasn't causing any interference. Otherwise, the FCC would have had a field day with them. But in each filing I've found when they shut down various locations, there was no mention of interference, only illegal operation.