Panasonic PT47WXD63 - 47" PROJECTION TV, Technical Manual

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LED Blinks Once (Vertical Protection)
Figure 43
A concentration of the electron bea spot of the CRT's phosphor, or a
eflection of the electron beam onto 's neck due to a loss of vertical
m on one
the CRT d
could damage the CRT. The vertical Pump-Up pulse is rectified by the diode
D407. The resulting DC voltage charges the capacitor C413. As long as the
charge is sufficient, the transistor Q406 remains on. A loss of or a drop in the
charge level causes Q406 to turn-off. This sends the voltage at its collector to the
DG-Board via the diode D409, pin 15 of the connector D2/A2, and pin 53 of the
connector A31 causing the MPU to activate shutdown and turn off the AC Relay
L801. R
81