[Popester]

You never know until you check some things out. SG613 sets were hard to fix, but not impossible. I'd dig out a DVM or VTVM before you pass judgement and let it become a parts set. Certainly worth investigating into it. My recommendation would be to use all OEM parts for the damper diode, HOT SG613, and not use equivalent. Our shop tried using equilavent parts for the SG613 and damper diode and sure enough the issue would show up again,but OEM parts worked and lasted better. This design didn't last thankfully all that long and us technicians were very grateful for that. Zeno and I aren't trying to frighten you out of repairing the set, but want to educate you about issues you could run into. Check the easy stuff first. Is the power cord check good with continuity? The on/off switch could be open. Look for bad solder joints. Take the back off and just give a real close visual look for discolored resistors, cracked solder joints, blown fuse, electrolytic caps with bulged top or electrolyte leaking out the bottom of the cap, or stuff like that. Maybe you have something real easy to fix. Good luck and keep us posted. Can you at least post a couples pictures of it?