Sony STR-VX4 - Page 37

SONY
STR-VX
Series
Circuit
Operation
2. Several seconds after power switch
is turned on
Base-emitter voltage of Q722 rises
to 0.6V.
Q723 Q726
Q722
ON-¢>Q725
ON-~Q719
OFF-—~input
muting
OFF
L
_
——
—~»speaker
protection
relay
ON
3.
Power
switch
is
turned
off
Q723 Q726
Q722
OFF-peQ725
OFF—»Q719
ON
(momentarily)—»input
muting
ON
(momentarily)
i
a
ee
aie
ey
speaker
protection
relay
OFF
B+ (40V)O
O
Q7i4
—{)
R732
bio
R745
i)
O ©
R73I 0707 whee
aL
a “@ R734 ue
\K_/ 0715 B-(-40V)
O
B-(-40V)
O B+ (40V)
{4 R79
Q723 fs A
—i5V
Relay
Drive,
Input
Muting
and
Impedance
Detector
Circuit.
11