POWER SUPPLY CIRCUIT
Commutating voltage from AC output rectified by D901A and produces approximately 300V to pin 3 of I901.
Current flowing through R904, R917, causes I901 pin 4 to initially turn on.
Secondary voltage are then induced winding V1 - V2 in T901, I901 supply voltage is obtained via R906, D906, C909
and applied to pin 4 of I901, thereby maintaining I902 switching operation. Secondary voltage in S1, S3 winding is
rectified by D951 to produce +B = 95V which is smoothed by C953. S2, S4 winding produces 16V from D952, and
this is smoothed by C956.
Error amplifier Q951 is set to a pre-determined level by resistor network R952 - R956, and reference voltage D957
Should the +B voltage rise, base voltage of transistor Q951 will become more positive, and this difference is ampli
fied by the error amplifier Q951. An output is applied to I901 feedback pin 1 through optocoupler (CTR) I902 an
controls ON time of I901 internal circuit . In this way, +B voltage is regulated and maintained at a constant level.
D973 offers protection that it should the voltage level rise excessively
When the standby mode is selected, pin 1 of I001 will go " low " . As a result Q954 and Q955 are turned off, and th
supply voltage for the horizontal start of pin 33 of I001 though R980/D980/R071 disappears. Therefore shutting
down the deflection drive stages of I001, deflection output stage will then cease for as long as the standb
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