It was either 'Free Radio North America', or 'WART' on shortwave. I can't recall for sure, I heard them both within a month or two.... but I kind of think WART was first. As I was already broadcasting TCS, I was much more focused on broadcasting than listening.
'WART' was more well-known as an AM pirate broadcasting to New York City. I caught them on shortwave, called his announced loop number, and recognized him as someone who had called The Crystal Ship's telephone loop number a few weeks before. Off-air he offered to do some work on our Knight T-150 transmitter which was having all kinds of fits, and did a great job on it for us, correcting many errors which the original kitbuilder had made, as well as replacing some aging parts. WART used a Johnson Valiant II on both shortwave and the top of the AM band at that time, around 1620.
'Free Radio North America' was on Thanksgiving Day 1982. They were quite powerful, broadcast station quality. Unfortunately, it is said that they were busted within a week, and never replied to my reception report.