Sony TC-WE425 Service Manual page 11

Record/Playback Head Azimuth Adjustment
Procedure:
1. Forward Playback Mode
test tape
P-4-A100
(10 kHz, –10 dB)
set
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 1 dB.
within
output
L-CH
1 dB
level
peak
R-CH
peak
screw
L-CH
position
peak
3. Playback Mode
test tape
P-4-A100
(10 kHz, –10 dB)
L-CH
set
R-CH
In phase 45˚
good
4. Change the reverse playback mode and repeat the steps 1 to 3.
5. After the adjustment, lock the adjustment screws with suitable
locking compound.
Adjustment Location: –record/playback head–
forward side
adjustment screws
DECK A DECK B
level meter
47 k Ω
+
–
LINE OUT
within
1 dB
screw position
R-CH
peak
oscilloscope
47 k Ω
V H
+ +
– –
47 k Ω
LINE OUT
Screen Pattern
90˚ 135˚ 180˚
wrong
reverse side
Tape Speed Adjustment
Procedure:
–Forward Playback Mode–
test tape
WS-48B
(3 kHz, 0 dB)
(High speed adjustment)
1. Set to test mode. (Refer to page 10.)
2. Set to FWD playback mode.
3. Twice pressing the HIGH/NORMAL switch.
4. Adjust RV316 (DECK A), RV416 (DECK B) so that the
frequency counter reading becomes 5,980 ± 20 Hz.
5. Release test mode after adjustment is completed.
(Normal speed adjustment)
1. Set to FWD playback mode.
2. Adjust RV317 (DECK A), RV417 (DECK B) so that the
frequency counter reading becomes 3,000 ± 10 Hz.
(Pitch control adjustment) (DECK A) (TC-WE525 only)
1. Push the PITCH CONTROL switch.
2. Set RV986 (PITCH CONTROL knob) to mechanical center.
3. Set to FWD playback mode.
4. Adjust RV318 so that the frequency counter reading becomes
2,990 ± 10 Hz.
Frequency difference between the beginning and the end of the tape
should be within ± 3%.
Frequency difference between the deck A and deck B the beginning
of the tape should be within ± 1.5%.
Adjustment Location: MAIN board (See page 13.)
Playback Level Adjustment
Procedure:
–Forward Playback Mode–
test tape
P-4-L300
(315 Hz, 0 dB)
Adjust DECK A : RV111 (L-CH), RV211 (R-CH) and
DECK B : RV121 (L-CH), RV221 (R-CH) so the level meter read-
ing becomes the adjustment limits below.
Adjustment Value:
LINE OUT level : –7.7 ± 0.5 dB (0.301 to 0.338 V)
Level difference between channels : within 0.5 dB
Confirm that the LINE OUT level does not change in playback mode
while changing the mode from playback to stop several times.
Adjustment Location: MAIN board (See page 13.)
– 11 –
DECK A DECK B
frequency counter
47 k Ω
+
set
–
LINE OUT
DECK A DECK B
level meter
47 k Ω
+
set
–
LINE OUT