Electrical Adjustments - Sony CX-LFA660 Service Manual

QQ
3 7 63 1515 0
DECK SECTION
1. Demagnetize the record/playback head with a head
demagnetizer.
2. Do not use a magnetized screwdriver for the adjustments.
3. After the adjustments, apply suitable locking compound to
the parts adjusted.
4. The adjustments should be performed with the rated power
supply voltage unless otherwise noted.
5. The adjustments should be performed in the order given in
this service manual. (As a general rule, playback circuit
adjustment should be completed before performing recording
circuit adjustment.)
6. The adjustments should be performed for both L-CH and R-
CH.
7. Switches and controls should be set as follows unless otherwise
specified.
Tape
P-4-A100
WS-48B
[Record/Playback Head Azimuth Adjustment]
Procedure:
1. Mode : Playback
test tape
P-4-A100
(10kHz, –10dB)
TE
L 13942296513
2. Turn the adjustment screw and check output peaks. If the peaks
do not match for L-CH and R-CH, turn the adjustment screw
so that outputs match within 1 dB of peak.
L-CH
output
peak
level
R-CH
peak
screw
position
www
.
http://www.xiaoyu163.com

ELECTRICAL ADJUSTMENTS

0 dB=0.775V
Signal Used for
10 kHz, –10 dB Azimuth Adjustment
3 kHz, 0 dB Tape Speed Adjustment
MAIN board
J201
speaker terminal
set
within
1 dB
L-CH R-CH
peak peak
x ao
y
i
http://www.xiaoyu163.com
SECTION 6
8
3. Mode: Playback
test tape
P-4-A100
(10kHz, –10dB)
4. After the adjustments, apply suitable locking compound to
the parts adjusted.
Adjustment Location: Record/Playback/Erase Head
level meter
Q Q
3 6 7 1 3
+
–
within 1dB
[Tape Speed Check]
Procedure:
screw
1. Turn the power on.
position
2. Insert the WS-48B into deck.
3. Press the TAPE nN button of deck.
4. Check the reading of frequency counter becomes 3000 ± 90
Hz.
Sample Value of Wow and flutter
u163
W.RMS (JIS) less than 0.3%
(test tape: WS-48B)
.
CX-LFA660/LFA770
2 9 9 4 2 8
MAIN board
J201
speaker terminal
L
set
R
Waveform of oscilloscope
45 ° 90 ° 135 °
in phase
good
1 5 0 5 8 2 9 9 4
adjustment screw
m
co
9 9
oscilloscope
180 °
wrong
2 8 9 9
17