Hello there Audiokarma members... I'm so pissed at myself!...i know better... After I made 5 attempts to get the idle current to stabilize a 8mv .... which I was successful everytime.. but after several days I'd notice the left Channel was weaker with the bass...so I'd check and sure enough the voltage was lower than the other channel.. had to readjust.. But yesterday's attempt was a big mistake! I shorted out the transistor and watched a couple of tiny transistors glow before I could shut down... So... I need to have a Professional that comes Highly Regarded & Recommended by Audiokarma members!... preferably in MICHIGAN.... so I can drive to Drop the Receiver off.... This Receiver means a lot to me! & Was like brand new before I had to try to adjust the idle current or Bias... HiFi Engine has the free service manual https://www.hifiengine.com/manual_library/technics/sa-600.shtml Anyway any help would be greatly appreciated i'd hate to have to sell it for parts or give up on it..... this Receiver means more to me than I can say, so much so that I am going to be selling one of my favorite long rifles to pay for it's repair "if it can be done".