Sony HD-XB4K Service Manual page 34

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3 7 63 1515 0
Record Bias Current Adjustment
Procedure:
1. Mode: Record
Pin 6 (L-CH) of IC1501 on the MAIN board.
Pin #¶ (R-CH) of IC1501 on the MAIN board.

1) 315 Hz

50 mV (–23.8 dB)
2) 10 kHz

AF OSC
600 Ω
attenuator
Pin 2 (GND) of ICN207 on the MAIN board.
2. Mode: Playback
recorded
portion
set
MAIN board
CN207 (Pin 1 : L-CH)
Confirm playback the signal recorded in step 1 become adjustable
limits as follows.
If these levels do not adjustable limits, adjustment the RV341 (L-
CH) and RV441 (R-CH) on the AUDIO board to repeat steps 1 and
2.
Adjustable limits: Playback output of 315 Hz to playback output
of 10kHz: 0±0.5 dB
TE
L 13942296513
Adjustment Location: AUDIO and MAIN boards
Record Level Adjustment DECK B
Procedure:
1. Mode: Record
Pin 6 (L-CH) of IC1501 on the MAIN board.
Pin #¶ (R-CH) of IC1501 on the MAIN board.
315 Hz, 50 mV (–23.8 dB)
AF OSC
600 Ω
attenuator
Pin 2 (GND) of CN207 on the MAIN board.
2. Mode: Playback
recorded
portion
set
MAIN board
CN207 (Pin 1 : L-CH)
Confirm playback the signal recorded in step 1 become adjustable
limits as follows.
If these levels do not adjustable limits, adjustment the RV1501
www
(L-CH) and RV1551 (R-CH) on the MAIN board to repeat steps 1
and 2.
Adjustable limits:
CN207 PB level: 47.3 to 53.1 mV (–24.3 to –23.3 dB)
.
Adjustment Location: MAIN board
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DECK B
blank tape
CN-123
set
level meter
+
–
(Pin 3 : R-CH)
blank tape
CS-123
set
level meter
+
–
(Pin 3 : R-CH)
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8
Adjustment Location:
[MAIN BOARD] (Component Side)
IC201
[AUDIO BOARD] (Conductor Side)
Record Bias Current
Adjustment
R L
RV301 ® L
RV441 RV341
RV401 ® R
Playback Level
Adjustment
– DECK B –
Q Q
3 6 7 1 3
u163
.
– 34 –
2 9 9 4 2 8
RV1501
1
IC1501
3
CN207
IC301
RV1551
Record Level
Adjustment
Tape Speed Adjustment
(NORMAL)
(HIGH)
RV651
RV652
®
RV311
L ®
Playback Level
Adjustment RV411
R ®
– DECK A –
1 5 0 5 8 2 9 9 4
m
co
9 9
CN205
®
2 8 9 9