Yamaha A-S700 Service Manual page 23

Note)
• Applying the power to this unit without correcting the
abnormality can be dangerous and cause additional
circuit damage.
To avoid this, if protection function has been activat-
ed the number of times which is set beforehand, the
power will not turn on even when the "POWER" key
is pressed.
a. PS (Power Supply) protection:
If protection function has been activated 3 times
continuously, the power will not turn on.
b. Amplifier DC voltage protection L/Rch:
If protection function has been activated 3 times
continuously, the power will not turn on.
c. I protection L/Rch:
If protection function has been activated 1 time,
the power will not turn on.
However, the power turns on when the protection
function worked due to short at the speaker termi-
nal.
d. TMP protection L/Rch:
The power turns on no matter how many times the
protection function has worked.
Note)
• The output transistors in each amplifier channel
should be checked for damage before applying
power of this unit.
• Amplifier current should be monitored by measuring
DC voltage across the emitter resistors for each
channel.
• Set this unit once to the "factory reset" state before
turning on the power again.
(For more information, refer to "Factory Reset"of
SELF-DIAGNOSTIC FUNCTION.)
A-S700
23