Chosen Solution
1976 Technics SA-5550 stereo receiver was working perfectly. But then I used air blaster on it to clear out dust, and the the “anti-shock timing circuit” stopped functioning. The literature on this describes the anti-shock timing circuit as “helps eliminate annoying thumps in the speaker after turn-on by delaying turn-on of the speaker terminals”. What is the remedy? Is it possible dust got lodged in the circuit?
mchlgrblsk ‘’this “anti-shock timing circuit” would most likely be accomplished by either some capacitors, transistors or relays. TR703-TR707 are listed as protection transistor You’ll have to take a look at your boards for any damaged looking components. There should be SUP8450 board in your amp. That is the one for the power source and speaker protection. It could be dust that shortened things out. Of course also possible that the “air blaster” did move some things around. It might help if you post some pictures with your question. May be someone can see more.
