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:
The first path sees the supply voltage being
fed via resistor R861 to the standby relay
RL801 and the relay winding to the collector
of transistor Q853. Transistor
controlled by Q854, is responsible for
switching the TV into and out of standby
mode
under
microprocessor IC,
When
Q853
is switched ON current flows
through the winding of the relay and
collector / emitter junction of Q853. This
current flow causes the relay contact to
close feeding the mains supply to the bridge
rectifier and the switched mode power
supply IC IC801.
A 12V supply is also fed from the main
power supply via R863 and D871, this
supply being used to reduce the load on the
standby transformer when the TV is in
normal operation.
Q853
which is
the
control
of
the
IC1101
pin 52.
:
The second path is via resistor R862 to the
base of transistor Q852. This supply being
regulated by the zener diode D872 is used
as a base bias.
2.
The second path from the standby transformer
T802, that the supply voltage follows is via the
rectifying diode D867 and smoothing capacitor
C871. Here the supply is applied to the collector
of Q852. From the emitter of
supply is fed to the Microprocessor IC1101, the
EPROM IC1102, the EAROM
Link circuit consisting of transistors
Q1107.
This supply allows these circuits to operate
during standby which is required to process the
switch ON command from the remote control or
local keys, allowing the TV to be switched out of
standby, or to also process AV Link commands.
11
3DQDVRQLF
Q852
a 5V standby
IC1103
and AV
Q1104
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