Input/Output Levels And Impedance; Adjustment Sequence; Power Supply Check; Power Supply Voltage Check (Ma-388 Board) - Sony SLV-SE850 Service Manual

2-1-5.

Input/Output Levels and impedance

Video input: LINE-1 / LINE-3 IN(*1) / LINE-4 IN(*2)
EURO AV connector
Input signal: 1Vp-p, 75 ohms, unbalanced, sync
negative
LINE-2 IN / LINE-3 IN(*2), Phono jack
Input signal: 1Vp-p, 75 ohms, unbalanced, sync
negative
Video output: LINE-1, EURO AV connector
Output signal: 1Vp-p, 75 ohms, unbalanced, sync
negative
LINE-2 OUT(*3), Phono jack
Output signal: 1Vp-p, 75 ohms, unbalanced, sync
negative
Audio input: LINE-1 / LINE-3 IN(*1) / LINE-4 IN(*2)
EURO AV connector
Input level: –6.3dBs
Input impedance: more than 47 kilohms
LINE-2 IN/ LINE-3 IN(*3), Phono jack
Input level: –7.5dBs
Input impedance: more than 47 kilohms
(0dBs=0.775Vrms)
Audio output:LINE-1, EURO AV connector
Output level: –6.3dBs at load impedance 47 kilohms
Output impedance: less than 10 kilohms
LINE-2 OUT(*3), Phono jack
Output level: –7.5dBs at load impedance 47 kilohms
Output impedance: less than 10 kilohms
*1 : SLV-SE850/SF900 model only
*2 : SLV-SF990 model only
*3 : SLV-SF950/SF990 model only
2-1-6.

Adjustment Sequence

The adjustments should be performed in the following sequence.

Power Supply Check

System Control Adjustment
Servo System Adjustments
Video System Check
Audio System Adjustments
2-2. POWER SUPPLY CHECK
2-2-1.

Power Supply Voltage Check (MA-388 board)

Mode
Measuring instrument
38V check
Measurement point
Specified value
13V check
Measurement point
Specified value
MTR12V check
Measurement point
Specified value
CAPSTAN VCC check
Measurement point
Specified value
SW12V check
Measurement point
Specified value
D6V check
Measurement point
Specified value
SW5V check
Measurement point
Specified value
–30V check
Measurement point
Specified value
+F, –F check
Measurement point
Specified value
[Check Method]
1) Check that each power supply voltage satisfies the specified
value.
6-2
E-E
Digital voltmeter
CN601 pin 5
39 ± 3Vdc
CN601 pin qs
13.55 ± 0.45Vdc
CN601 pin 6 or 7
13.55 ± 0.45Vdc
CN601 pin 8 or 9
13.0 ± 0.5Vdc
CN601 pin qh
12.0 ± 0.3Vdc
CN601 pin qk
5.9 ± 0.15Vdc
CN601 pin 3 or 4
5.15 +1.0 Vdc
–0.2
CN601 pin ws
–29 ± 3Vdc
+ probe: CN601 pin w;
– probe: CN601 pin wd
4.6 ± 0.5Vdc