I bought a 1976 Technics Reciever Model SA-8500X 4-Channel Quad Reciever was there Top of line model. I bought it off of EBay for $450.00 & I didn’t get a working unit. The Person let the time run out on it. The Exterior is 100% Mint Condition not a scratch anywhere on it. But I took the case off of it & I found the Trouble it it’s the 2nd Heat SInk Circuit Board. It’s been Repaired Once before. (2 of the Green Slow Blow Fuses & a Resistor have been replaced. I was taken advantage of because I’m legelly Blind. So I am depressed over this can anyone tell me what to do? I what to get it up an Running again.