Dc-Dc Converter Adjustment; Frequency Adjustment; Voltage Adjustment; Other Voltage Checks - Sony XVM-R70 Service Manual

5-4. DC-DC CONVERTER ADJUSTMENT

5-4-1. Frequency Adjustment

Adjustment Method:
1) Connect frequency counter between TP801 (+) and TP803 (–).
2) Adjust RV801 so that the reading on the counter stands at the
specified value.
Specified value: 242 ± 3 kHz
Adjustment location: LCD board
5-4-2. 5V Voltage Adjustment
Adjustment Method:
1) Connect digital voltmeter between TP806 (+) and TP803 (–).
2) Adjust RV802 so that the reading on the counter stands at the
specified value.
Specified value: 5.15 ± 0.02 V
Adjustment location: LCD board

5-4-3. Other Voltage Checks

Checking Method:
1) Connect digital voltmeter between TP807 (+) (Vdd) and
TP803 (–).
2) Verify that the reading on the voltmeter is at 3.50 ± 0.2 V.
3) Connect digital voltmeter between TP805 (+) (Vgh) and
TP803 (–).
4) Verify that the reading on the voltmeter is at 17.5 ± 1.5 V.
5) Connect digital voltmeter between TP804 (+) (Vss) and
TP803 (–).
6) Verify that the reading on the voltmeter is at –12.0 ± 1.5 V.
Checking location: LCD board

5-5. PLL ADJUSTMENT

5-5-1. Frequency Adjustment
Adjustment Method:
1) Connect digital voltmeter between TP616 (+) and TP600 (–).
2) Adjust RV600 so that the reading on the counter stands at the
specified value.
Specified value: 2.5 ± 0.15 V
Adjustment location: LCD board

5-5-2. Frequency Check

Checking Method:
1) Connect frequency counter between TP612 (+) and TP600 (–).
2) Verify that the reading on the counter is at 14.4 ± 0.2 MHz.
Checking location: LCD board

5-6. INVERTER HIGH VOLTAGE CHECK

Condition: DIMMER switch OFF

5-6-1. Voltage Check

Checking Method:
1) Connect oscilloscope between TP853 (+) and TP854 (–) using
high voltage proof probes (100:1).
2) Verify that the reading on the oscilloscope is at 550 ± 150 V
(rms).
Checking location: LCD board
5-6-2. Frequency Check
Checking Method:
1) Connect oscilloscope between TP853 (+) and TP854 (–) using
high voltage proof probes.
2) Verify that the reading on the oscilloscope is at 68 ± 3 kHz.
Checking location: LCD board

5-7. OSD DOT CLOCK CHECK

1. Dot Clock Check
Checking Method:
1) Connect frequency counter between TP405 (+) and TP404 (–).
2) Verify that the reading on the counter is at 6.5 ± 0.2 MHz.
Checking location: LCD board

5-8. NTSC SUBCARRIER CHECK.

1. Subcarrier Check
Checking Method:
1) Press the INPUT key on the remote controller and enter the
NTSC mode using the R and
2) Connect frequency counter between TP508 (+) and TP500 (–).
3) Verify that the reading on the counter is at 3.579545 MHz ± 100
Hz.
Checking location: LCD board

5-9. PAL SUBCARRIER CHECK

1. Subcarrier Check
Checking Method:
1) Press the INPUT key on the remote controller and enter the
R
PAL mode using the and
2) Connect frequency counter between TP508 (+) and TP500 (–).
3) Verify that the reading on the counter is at 4.433619 MHz ± 100
Hz.
Checking location: LCD board

5-10. IR TRANSMITTER CHECK

1. VCO Frequency Check
Checking Method:
1) Input 400 Hz, –20dB V to TP354 for L channel and TP350 for R
channel.
2) Connect frequency counter to TP353 for L channel and TP352
for R channel.
3) Verify that the reading on the counter stands at the specified value.
Specified value: 2.3 MHz ± 45 kHz for L channel
2.8 MHz ± 45 kHz for R channel
Checking location: LCD board
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