Compaq MV7540, Руководство по обслуживанию

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HP MV7540
17
6-3. No Raster, Indicator Is Green
If the indicator of functional key is normal when there’s
no signal.
Check CPU control circuit
1. 5v power supply circuit
2. Rest circuit
3. oscillator
4.I
2
C bus circuit.
Connect with signal and check the voltage of G1 is
between -25 and -65V.
Check the voltage is
at the normal range
Check the voltage is
about 0V
Check the voltage is
about -80v
.
Press the menu key and look if the
indicator is under control.
Check the voltage at base of
Q705 is normal.
Check if it is high level
at pin16 of IC101.
Check the brightness
control circuit as
Q705, R705.
Check MUTE circuit as
D420, IC101
Check the signal cable
YES
NO
NO
YES
Section2
Section1
NO
YES
YES
NO