I have had mine 40 years, the only fault ever was when I connected a faulty cassette deck I was repairing for someone. (Bloody chassis was live) That stuffed the speaker protection circuit too. Hope you enjoy it as much as I do. FWIW I changed the electrolytics on the little pre-amp board for tantalum beads maybe 35 years ago, super quiet now. (Tants seem more reliable when not subject to inrush current). The power output of the JAS-71 is far more than ratings suggest.... has a lot more punch than my Quad 405s
I've had similar stuff like that happen to me with amateur radio equipment. You've got to wonde why some people mess with stuff! Still have the JVC amp and it's due to be my next recapping project. I've always had a feeling this baby does way more than what JVC would suggest :)
Andrew Page, the cassette deck had been looked at by someone else who had decreed that it needed a new mains transformer. Naturally I didn’t believe it, until after the bang. The amplifier can swing about 32vrms into 4 ohms with one channel driven. Ham gear can be a whole murky world of deceit and lies, it can be fun to repair...but preferably for fun and not money! 73