In article .com,
steve wrote:
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.

Usually looking for a DC offset to protect the speakers. Maybe also
oscillation. A scope should tell all.

--
*Money isn't everything, but it sure keeps the kids in touch *

Dave Plowman London SW
To e-mail, change noise into sound.