Hi Guys, I picked up a kenwood ka-54 amp today at the garage sale. As you might expect the first thing I do is plug it in and turn it on before I buy it. Of course I listen for the telltale click for the protection circuit. There was none so I almost didn't buy it. Since I paid five bucks for it, I took a chance. Well it works fine, save needing a de-oxit bath. I thought most amps after the 70's had protection circuits. Any thoughts?