Sony HCD-VP1 Service Manual page 12

Playback level Confirmation and Adjustment
Procedure:
Mode: Playback
test tape
P-4-L300
(315 Hz, 0 dB)
set
MAIN board
LINE OUT jack (PJ301)
L-CH, R-CH
Confirm playback level is within specification values as follows.
If these levels are out of specification values, adjust the RV151
(L-CH) and RV251 (R-CH) on the MAIN board so that the level
meter reading become within specified value.
Specified value:
PJ301 PB level: 301.5 to 338.3 mV (–8.2 to –7.2 dB) level differ-
ence between the channels: within ±0.5 dB
Adjustment Location: MAIN board
REC Bias Confirmation and Adjustment
Procedure:
1. Mode: Record
MAIN board
MD IN jack (PJ301)
L-CH, R-CH
1) 315 Hz
2) 10 kHz
AF OSC
600 Ω
attenuator
2. Mode: Playback
recorded
portion
set
3. Confirm playback the signal recorded in step 1 become speci-
fied value as follows.
If these values are out of specification values, adjust the RV153
(L-CH) and RV253 (R-CH) on the MAIN board to repeat steps
1and 2.
Specified value: Playback output of 315 Hz to playback output
of 10 kHz: ± 0.5 dB
Adjustment Location: MAIN board
12
level meter
+
–


50 mV (–23.8 dB)

blank tape
CN-123
set
level meter
+
–
MAIN board
LINE OUT jack (PJ301)
L-CH, R-CH
REC Level Confirmation and Adjustment
Procedure:
1. Mode: Record
MAIN board
MD IN jack (PJ301)
L-CH, R-CH
315 Hz, 50 mV (–23.8 dB)
AF OSC
600 Ω
attenuator
2. Mode: Playback
recorded
portion
set
MAIN board
LINE OUT jack (PJ301)
L-CH, R-CH
3. Confirm playback the signal recorded in step 1 become speci-
fied value as follows.
If these values are out of specification values, adjust the RV252
(R-CH) and RV152 (L-CH) on the MAIN board to repeat steps
1 and 2.
Specified value:
PJ301 PB level: 47.2 to 53.0 mV (– 24.3 to – 23.3 dB)
Adjustment Location: MAIN board
– MAIN Board (Conductor Side) –
RV252 (R)
IC352
RV152 (L)
RV251 (R)
Playback Level
RV151 (L)
RV253 (R)
RV153 (L)
blank tape
CS-123
set
level meter
+
–
LINE OUT (L/R)
PJ301 MD IN (L/R)
VIDEO IN (L/R)
REC Level
REC Bias