I'm hoping that there may be somebody with a 5 channel amplifier Yamaha
DSP A-990. I like my old machine, 6 years old, a fantastic sound and
video processor. Happened to short the outputs and blew most of the 14
power darlington transistors. I have repaired with newer equivalents
and all e-c-b voltages are OK, but 5 seconds after start, there is a
safety relay that switches power off. I can't figure out why and what
the sensors react on. Complicated electronics. Now I just wonder if
someone happen to have such a machine and if there is also someone who
have schematics. Yamaha don't not respond positively on my request, say
they have no service on such a obsolete amplifier.

Thanks!