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PHILIPS

Check the output of the bridge rectifier - voltage on the capacitor 2508 should be approximately 300 V. If the voltage is missing, check the fuse and diode bridge 1500 6505 . If the fuse is blown - check key transistor 7518 for short circuit or an open resistor 3518 . If the voltage of +300 V is - check the drive voltage
7520 chips at the pin . 1. It should be approximately 13 V.
If there is no voltage start - check for an open resistor and zener 3510 6510 for short .
If the voltage on pin 1 IC 7520 is - oscilloscope check the voltage at the pin . 9 transformer 5545 . and serviceability of the resistor 3529 and diode 6540 .
Check gate signal key transistor 7618 (reference point P2) . In the absence of signal transistor check signal output circuit 7520 ( vyv. 3 ) and the serviceability of the resistor 3525 and diode 6514 .
Stdbycon ( b vyv. MP output ) • signal is generated
microprocessor in the transition to standby mode or when protection is activated. At this signal BG1 goes into standby mode . In normal operation the pin. 6 MP High Voltage (3.3V ) Standby - low ;
Power down ( vyv. 69 MP , input) - BP signal is generated , during normal operation the signal level is 3.3V standby signal changes its value at 10 Hz , while the positive half-wave duration of 5 ms . When a fault in the circuit of +12 V (MainAux) signal is low .
A current sensor circuit 12 to the resistor 3564 is (block A1). When the current increases above 1 , b 2 ... A trigger transistors 7564 and 7562 switches , opening the transistor 7561 .

Circuit Tuner Control

Sel-IF-LL'M-trap ( vyv. 3 MP output) - control signal for selecting the filter corresponding to the system of a television signal
Low signal corresponds to :
Western Europe selected signals PAL B / G, I; SECAM L / L ';
Eastern Europe selection system PAL B / G;
for Southeast Asian selection system NTSC M. High level signal is equal to:
Western Europe selection systems SECAM L / L ', L'-NICAM;
Eastern Europe selection system PAL D / K;
for Southeast Asia PAL B / G, D / K, I.

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