Analog Audio Input Adjustment - Sony MAV-555 Maintenance Manual

CH-4 adjustment
1. Short TP802 (L-3) /AD-160 board and E801 (L-3) /
AD-160 board using a shorting clip.
2. Connect and set an oscilloscope as follows.
CH-2, _slope
TRIG :
3. Equipment : Oscilloscope
Test point : TP409 (J-4)/AD-160 board
Adj. point : 1RV804 (J-3)/AD-160 board
Spec.: As specified by the waveform of TP409
(AUDIO CH-4) shown below.
4. Remove the shorting clip from AD-160 board TP802
and E801.
TP407
16-Bit
TP408
(OK)
Audio CH-1
16-Bit
TP409
(OK)
Audio CH-3
NG
NG
A B C D E
1
2
1 1
RV501
1 1
3
TP502
RV504 RV604
4
5
6
7
8
9
MAV-555
4-Bit 16-Bit 4-Bit
Audio CH-2
4-Bit 16-Bit 4-Bit
Audio CH-4
F G H J K L
1 1
E801
E401
TP409
AD-160 board (A side)

4-6-2. Analog Audio Input Adjustment

Preparation
. AUDIO REC/PB level control knob (CH-1 to CH-4)/
meter panel
. INPUT button/meter panel
. ANALOG CH-1 to CH-4 buttons/meter panel
. Press either R1 or R2 button on the meter panel in
accordance with the port to which the AD-160 board is
connected.
Adjustment Procedure
Set an audio analyzer as follows.
Adjustment mode : LEVEL, dBm (600 Z)
Input filter : 80 kHz low-pass filter
CH-1 adjustment
1. Short TP501 (D-2) /AD-160 board and E501 (B-3) /
AD-160 board using a shorting clip.
2. Connect the audio signal (1 kHz, +4 dBm) to the
AUDIO INPUT CH-1 connector/BKMA-570 of the
port to which the AD-160 board is connected.
3. Press the MONITOR button of the MONITOR
SELECT block on the meter panel. Press then the CH-
1 button to turn it on. (The CH-1 signal is outputted to
the MONITOR OUT-L connector.)
n
Turn off the ANALOG CH-2 to CH-4 buttons.
4. Equipment : Audio analyzer
Test point : AUDIO MONITOR OUT-L connector/
rear panel
Adj. point : 1RV501 (C-3) /AD-160 board
+4.0 ± 0.1 dBm (600 Z load)
Spec. :
5. Remove the shorting clip from AD-160 board TP501
and E501.
6. Equipment : Audio analyzer
Test point : AUDIO MONITOR OUT-L connector/
rear panel
Adj. point : 1RV502 (D-3) /AD-160 board
+4.0 ± 0.1 dBm (600 Z load)
Spec. :
4-6. AD-160 Board Adjustment
→ PRESET
→ Lights up
→ Lights up
4-15 (E)