Input/Output Levels And Impedance; Adjustment Sequence; Power Supply Check; Output Voltage Check (Ma-397 Board) - Sony SLV-LX80S Service Manual

2-1-5.

Input/Output Levels and Impedance

Video input: LINE IN
Input signal: 1 Vp-p, 75 ohms, unbalanced,
sync negative
Video output: LINE OUT
Output signal: 1 Vp-p, 75 ohms, unbalanced,
sync negative
Audio input: LINE IN
Input level: –7.5 dBs
(0 dBs= 0.775 Vrms)
Input impedance: more than 47 kilohms
Audio output:LINE OUT
Standard level: –7.5 dBs at load impedance 47
kilohms
Output impedance: less than 10 kilohms
2-1-6.

Adjustment Sequence

The adjustments should be performed in the following sequence.

Power Supply Check

Servo/Video System Adjustments
Audio System Adjustments
2-2. POWER SUPPLY CHECK
2-2-1.

Output Voltage Check (MA-397 Board)

Mode STANDBY
+30 V Check
Measurement point C671 3
Specified value 31.0 to 39.0 V
–11 V Check
Measurement point Anode of D420
Specified value –12.5 to – 9.5 V
D+6 V Check
Measurement point Collector of Q674
Specified value 5.56 to 6.25 V
Mode E-E
Measuring Instrument Digital voltmeter
SW+12 V Check
Measurement point IC660 pin 2
Specified value 11.7 to 12.3 V
SW+5 V Check
Measurement point Emitter of Q662
Specified value 4.8 to 5.4 V
MTR12 V Check
Measurement point Collector of Q600
Specified value 12.5 to 14.5 V
F Check
Measurement point ND420 e; to 1
Specified value 2.0 to 5.0V
[Check Method]
1) Each of these supply voltages must meet its specified value.
6-2