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– 16 –
REC Bias Adjustment
DECK B
Procedure:
1. Mode: Record
FUNCTION: VIDEO
2. Mode: Playback
3. Confirm playback the signal recorded in step 1 become speci-
fication values as follows.
If these values are out of specification values, adjust the RV341
(L-CH) and RV441 (R-CH) on the AUDIO board to repeat
steps 1and 2.
Specification values: Playback output of 315 Hz to playback
output of 10 kHz: ± 0.5 dB
Adjustment Location: AUDIO board
REC Level Adjustment
DECK B
Procedure:
1. Mode: Record
FUNCTION: VIDEO
2. Mode: Playback
3. Confirm playback the signal recorded in step 1 become speci-
fication values as follows.
If these values are out of specification values, adjust the RV301
(L-CH) and RV351 (R-CH) on the MAIN board to repeat steps
1 and 2.
Specification values:
J101 PB level: 47.2 to 53.0 mV (–24.3 to –23.3 dB)
Adjustment Location: MAIN board
– MAIN BOARD (Conductor Side) –
– AUDIO BOARD (Component Side) –
– LEAF SW BOARD (Component Side) –
attenuator
set
MAIN board
VIDEO (AUDIO) IN jack (J101)
L-CH, R-CH
1) 315 Hz
2) 10 kHz
50 mV (–23.8 dB)
600
Ω
blank tape
CN-123
AF OSC
+
–
set
recorded
portion
MAIN board
MD OUT jack (J101)
L-CH, R-CH
level meter
set
MAIN board
VIDEO (AUDIO) IN jack (J101)
L-CH, R-CH
315 Hz, 50 mV (–23.8 dB)
blank tape
CS-123
600
Ω
attenuator
AF OSC
+
–
set
recorded
portion
MAIN board
MD OUT jack (J101)
L-CH, R-CH
level meter
RV301
L
RV351
R
IC301
REC LEVEL
J101
VIDEO (AUDIO) IN
(L/R)
MD OUT
(L/R)
RV401
RV301
RV341
RV311
RV411
IC602
CN601
L
R
R L
RV441
PB LEVEL
– DECK B –
REC BIAS
L
R
PB LEVEL
– DECK A –
TAPE SPEED
RV1002
RV1001
(NORMAL) (HIGH)
CN1001