Hello all. I have a Peavey amp that I can use if I can fix it. It had a blown fuse in it so I replaced it and powered it up. The hum was very loud without any speakers hooked up. I only kept the power on for a couple secs. The new fuse did not blow. I opened up the amp and everything looks fine inside. The amp is a 1982 model, schematic 400BH. Some output transistors are known to fail on these older amps, but I sure can use some input from you guys. Let me know what you think.