How long has the Ampeg PBC-228 been around?

I played an Ampeg PBC-228 yesterday at Chuck Levin's. That little box is a lady killer! For roughly 600 bucks you get a 35 pound, 200 watt 2x8 combo amp, and it sounds really, really nice. I was surprised because I had never even seen or heard of one before. Are these new or have I just had blinders on? In any case, it was an easy one-arm lift with a top mounted handle, and the chassis looked pretty sturdy. I didn't get to push it though, out of respect for the fact that players were actually keeping their volume levels under control :0