15
MV-65ST
SECTION 5
ELECTRICAL ADJUSTMENTS
1.
DC/DC CONVERTER ADJUSTMENT
1-1. Frequency Adjustment
Setting:
Procedure:
1. Connect an oscilloscope or frequency counter to the TP802
and TP804 on the MONITOR board.
2. Check that the voltage between TP951 (
−
) and TP952 (+) is
14.4 V. Press the
[POWER]
button to turn the power on.
3. Adjust the RV801 on the MONITOR board so that the value
of oscilloscope or frequency counter becomes 243 kHz
±
3 kHz.
1-2. 5V Voltage Adjustment
Setting:
Procedure:
1. Connect a digital voltmeter to the TP804 and TP807 on the
MONITOR board.
2. Check that the voltage between TP951 (
−
) and TP952 (+) is
14.4 V. Press the
[POWER]
button to turn the power on.
3. Adjust the RV803 on the MONITOR board so that the value
of digital voltmeter becomes 5.05 V
±
0.03 V.
1-3. Other Voltages Check
Setting:
Procedure:
−
Vdd Voltage Check
−
1. Connect a digital voltmeter to the TP804 and TP808 on the
MONITOR board.
2. Check that the voltage between TP951 (
−
) and TP952 (+) is
14.4 V. Press the
[POWER]
button to turn the power on.
3. Check that the value of digital voltmeter is 3.45 V
±
0.2 V.
−
Vgh Voltage Check
−
4. Connect the digital voltmeter to the TP804 and TP806 on the
MONITOR board.
5. Check that the value of digital voltmeter is 17.5 V
±
1.5 V.
−
Vss Voltage Check
−
6. Connect the digital voltmeter to the TP804 and TP805 on the
MONITOR board.
7. Check that the value of digital voltmeter is –12.0 V
±
1.5 V.
2.
PLL ADJUSTMENT
Setting:
Procedure:
1. Connect a digital voltmeter to the TP601 and TP602 on the
MONITOR board.
2. Check that the voltage between TP951 (
−
) and TP952 (+) is
14.4 V. Press the
[POWER]
button to turn the power on.
3. Adjust the RV601 on the MONITOR board so that the value
of digital voltmeter becomes 2.5 V
±
0.15 V.
3.
INVERTER HIGH VOLTAGE CHECK
Setting:
Procedure:
−
High Voltage Check
−
1. Connect a digital voltmeter (for withstand high voltage) to the
TP853 and TP854 on the MONITOR board.
2. Check that the voltage between TP951 (
−
) and TP952 (+) is
14.4 V. Press the
[POWER]
button to turn the power on.
(DIMMER: off)
3. Check that the value of digital voltmeter is 550 V
±
150 V (rms).
−
Frequency Check
−
4. Connect an oscilloscope (use a probe for withstand high volt-
age) to the TP853 and TP854 on the MONITOR board.
5. Check that the frequency of oscilloscope is 66 kHz
±
2.5 kHz.
4.
OSD DOT CLOCK CHECK
Setting:
Procedure:
1. Connect a frequency counter (high impedance) to the TP403
and TP405 on the MONITOR board.
2. Check that the voltage between TP951 (
−
) and TP952 (+) is
14.4 V. Press the
[POWER]
button to turn the power on.
3. Check that the value of frequency counter is 6.5 MHz
±
0.2
MHz.
+
–
oscilloscope
or
frequency counter
MONITOR board
TP802
TP804
+
–
digital voltmeter
MONITOR board
TP807
TP804
+
–
digital voltmeter
MONITOR board
TP805/TP806/TP808
TP804
+
–
digital voltmeter
MONITOR board
TP601
TP602
+
–
digital voltmeter
MONITOR board
TP853
TP854
+
–
frequency counter
MONITOR board
TP403
TP405
