Mitsubishi C-6919 Service Manual page 34

3.5.8 Health Check Circuit
The health check circuit, 10cated on the PCB-DEFL,
functions to illuminate a Light Emitting Diode (LED),
D991 when the CRT anode high voltage circuit and +lOOV
power supply are operating properly.
The voltage generated across capacitor C306 is
~btained from the rectified retrace pulse (0302)
generated by high voltage transformer and is the
voltage source for LED illumination.
Transistor Q305 is a voltage regulator which outputed
+18V.
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