Read Sony HCD-W55 / MHC-W55 / MHC-W77AV Service Manual online
– 7 –
2. Turn the adjustment screw for the maximum output levels. If
these levels do not match,turn the adjustment screw until both of
output levels match together within 1dB.
output levels match together within 1dB.
L-CH
peak
peak
R-CH
peak
peak
L-CH
peak
peak
R-CH
peak
peak
Screw
position
position
output
level
level
within
1 dB
1 dB
within
1 dB
1 dB
screw angle
3. Playback Mode
test tape
P-4-A100
(10kHz, –10dB)
P-4-A100
(10kHz, –10dB)
V
H
in phase 45
°
90
°
135
°
180
°
good
wrong
set
L-CH
R-CH
screen pattern
L
R
Output level measurement point
(see page 6 )
(see page 6 )
4. Change the review playback mode and repeat the steps 1 to 3.
5. After the adjustment, lock the adjustment screw with suitable
5. After the adjustment, lock the adjustment screw with suitable
locking compound.
Adjustment Location :
– record/playback head (Deck A and B) –
test tape
WS-48B
(3kHz, 0dB)
WS-48B
(3kHz, 0dB)
+
–
set
frequency counter
Output level measurement point
(see page 6 )
(see page 6 )
Speed
Deck
Adjustment
Frequency counter
*High
A
RV652
5,970 to 6,030Hz
B
RV652
Normal
A
RV651
2,940 to 3,090Hz
B
RV651
test tape
P-4-L300
(315Hz, 0dB)
P-4-L300
(315Hz, 0dB)
Deck A is RV311 (L-CH) and RV411 (R-CH), deck B is RV301 (L-
CH) and RV401 (R-CH) so that adjustment within adjustment level as
follows.
CH) and RV401 (R-CH) so that adjustment within adjustment level as
follows.
Adjustment Level :
LINE OUT level : – 3.5
LINE OUT level : – 3.5
±
2.0dB (0.41 to 0.65V)
Level Difference between Channels : within 0.5dB
Confirm the OUTPUT level does not change in playback mode while
changing the mode from playback to stop several times.
changing the mode from playback to stop several times.
Adjustment Location : AUDIO board.
(see page 8)
set
VTVM
+
–
Output level measurement point
(see page 6 )
(see page 6 )
Tape Speed Adjustment
DECK A DECK B
Procedure :
r
Perform high speed adjustment before normal speed adjustment.
Mode : Playback
Mode : Playback
* Continue to press HIGH SPEED DUBBING switch (S266) in
playback mode : High speed playback.
Frequency difference between the begining and the end of the tape
should be within
should be within
±
3%.
Frequency difference between deck A and deck B the bigining of
the tape should be within 1.5%.
the tape should be within 1.5%.
Adjustment Location : AUDIO board.
(see page 8)
Playback Level Adjustment
DECK A DECK B
Procedure :
–FWD Playback Mode–
–FWD Playback Mode–
Fowerd
side
Reverse
side
Adjustment screws
Oscilloscope
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