Sony CX-LDB30 Service Manual page 21

3. Mode: Playback
MAIN board
SPEAKER terminal (J201)
test tape
L-CH
P-4-A100
(10 kHz, –10 dB)
L-CH
set
R-CH
R-CH
waveform of oscilloscope
in phase 45 °
good
4. After the adjustments, apply suitable locking compound to
the parts adjusted.
Adjustment Location: Record/Playback/Erase Head
adjustment screw
Note: Refer to "3-9. Cassette Panel" (see page 11)
Tape Speed Check
Mode: Playback
test tape
WS-48B
(3 kHz, 0 dB)
set
MAIN board
SPEAKER terminal (J201)
L-CH, R-CH
1. Insert the WS-48B into deck.
2. Press the TAPE N button of deck.
3. Confirm that the frequency counter reads 3000 ± 90 Hz.
Sample Value of Wow and flutter: 0.3% or less W.RMS (JIS)
oscilloscope
V H
90 ° 135 ° 180 °
wrong
frequency counter
+
–
(WS-48B)
Record Bias Adjustment
Procedure:
1. Record mode
MAIN board
AUX IN (J291)

1) 315 Hz

2) 10 kHz

AF OSC
600 Ω
attenuator
2. Mode: Playback
i-Bass OFF
BASS 0
TREBLE 0
recorded
portion
set
MAIN board speaker terminal (J201)
3. Confirm playback the signal recorded in step 1 become
adjustment level as follows.
Adjustment level: Playback output of 315 Hz to playback output
of 10 kHz: 0 ± 1.0 dB (0 ± 4.5mV).
CX-LDB30/LDB50
50 mV (–23.8 dB)
blank tape
CN-123
set
level meter
+
–
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