Lots of loud popping from my Chromacolor II...

Remember that 1977 Zenith Chromacolor II I got a few months ago? http://audiokarma.org/forums/showthr...313#post694313

Been working great till today. I turned it on. Picture started coming up normally, and as I walked away, followed by numerous *POP POP POW POP* as I ran to go shut it off. The picture was still displayed, but it was shrinking in and out violently as it did that.

I took the back off and gave it a quick lookover. I don't see or smell anything. I did put it back together and very quickly just turned it on. It didn't pop or explode, but now makes a sickly buzzing sound from the HV area. I immediately shut it off.

Anyone have an experience with this, to help narrow down the problem or what to look for? I've never had this happen before.