Sony HCD-MJ1 / HCD-MJ1A Service Manual ▷ View online
– 17 –
6-8. Focus Bias Adjustment
Adjusting Method :
1. Load a continuously recorded disc (Refer to “6-4. Creating MO
1. Load a continuously recorded disc (Refer to “6-4. Creating MO
Continuously Recorded Disc”.)
2. Rotate the JOG dial and display “CPLAY MODE”.
3. Press the YES button twice and display “CPLAY MID”.
4. Press the NO button when “C1 = AD = ” is displayed.
5. Rotate the JOG dial and display “FBIAS ADJUST”.
6. Press the YES button and display “ / a = ”.
3. Press the YES button twice and display “CPLAY MID”.
4. Press the NO button when “C1 = AD = ” is displayed.
5. Rotate the JOG dial and display “FBIAS ADJUST”.
6. Press the YES button and display “ / a = ”.
The first four digits indicate the C1 error rate, the two digits after
[/] indicate ADER, and the 2 digits after [a =] indicate the focus
bias value.
[/] indicate ADER, and the 2 digits after [a =] indicate the focus
bias value.
7. Rotate the JOG dial in the clockwise direction and find the focus
bias value at which the C1 error rate becomes 220.
8. Press the YES button and display “ / b = ”.
9. Rotate the JOG dial in the counterclockwise direction and find
9. Rotate the JOG dial in the counterclockwise direction and find
the focus bias value at which the C1 error rate becomes 220.
10.Press the YES button and display “ / c = ”.
11.Check that the C1 error rate is below 50 and ADER is 00.
11.Check that the C1 error rate is below 50 and ADER is 00.
Then press the YES button.
12.If the “( )” in “ - - ( )” is above 20, press the YES
button.
If below 20, press the NO button and repeat the adjustment from
step 2 again.
If below 20, press the NO button and repeat the adjustment from
step 2 again.
13.Press the NO button and press the MD
§ button to remove the
continuously recorded disc.
Note 1 :
The relation between the C1 error and focus bias is as shown
in the following figure. Find points a and b in the following
figure using the above adjustment. The focal point position
c is automatically calculated from points a and b.
figure using the above adjustment. The focal point position
c is automatically calculated from points a and b.
Note 2 :
As the C1 error rate changes, perform the adjustment using
the average vale.
the average vale.
C1 error
220
Focus bias value
(F, BIAS)
(F, BIAS)
b
c
b
6-9. Error Rate Check
6-9-1. CD Error Rate Check
6-9-1. CD Error Rate Check
Checking Method :
1. Load a test disc TDYS-1.
2. Rotate the JOG dial and display “CPLAY MODE”.
3. Press the YES button twice and display “CPLAY MID”.
4. “C1 = AD = - -” is displayed.
5. Check that the C1 error is below 20.
6. Press the NO button, stop playback, press the MD
1. Load a test disc TDYS-1.
2. Rotate the JOG dial and display “CPLAY MODE”.
3. Press the YES button twice and display “CPLAY MID”.
4. “C1 = AD = - -” is displayed.
5. Check that the C1 error is below 20.
6. Press the NO button, stop playback, press the MD
§ button, and
remove the test disc.
6-9-2. MO Error Rate Check
Checking Method :
1. Load a continuously recorded disc (Refer to “6-4. Creating MO
1. Load a continuously recorded disc (Refer to “6-4. Creating MO
Continuously Recorded Disc”.)
2. Rotate the JOG dial and display “CPLAY MODE”.
3. Press the YES button twice and display “CPLAY MID”.
4. “C1 = AD = ”is displayed
5. If the C1 error rate is below 50, check that ADER is 00.
6. Press the NO button, stop playback, press the MD
3. Press the YES button twice and display “CPLAY MID”.
4. “C1 = AD = ”is displayed
5. If the C1 error rate is below 50, check that ADER is 00.
6. Press the NO button, stop playback, press the MD
§ button, and
remove the continuously recorded disc.
6-10. Focus Bias Check
Change the focus bias and check the focus tolerance amount.
Checking Method :
1. Load a continuously recorded disc (Refer to “6-4. Creating MO
Checking Method :
1. Load a continuously recorded disc (Refer to “6-4. Creating MO
Continuously Recorded Disc”.)
2. Rotate the JOG dial and display “CPLAY MODE”.
3. Press the YES button twice and display “CPLAY MID”.
4. Press the NO button when “C1 = AD = ” is displayed
5. Rotate the JOG dial and display “FBIAS CHECK”.
6. Press the YES button and display “ / c = ”.
3. Press the YES button twice and display “CPLAY MID”.
4. Press the NO button when “C1 = AD = ” is displayed
5. Rotate the JOG dial and display “FBIAS CHECK”.
6. Press the YES button and display “ / c = ”.
The first four digits indicate the C1 error rate, the two digits after
[/] indicate ADER, and the 2 digits after [c =] indicate the focus
bias value.
Check that the C1 error is below 50 and ADER is 00.
[/] indicate ADER, and the 2 digits after [c =] indicate the focus
bias value.
Check that the C1 error is below 50 and ADER is 00.
7. Press the YES button and display “ / b = ”.
Check that the C1 error is not below 220 and ADER is not above
00 every time.
00 every time.
8. Press the YES button and display “ / a = ”.
Check that the C1 error is not below 220 and ADER is not above
00 every time.
00 every time.
9. Press the NO button, next press the MD
§ button, and remove the
continuously recorded disc.
Note 1 :
If the C1 error and ADER are above 00 at points a or b, the
focus bias adjustment may not have been carried out prop-
erly. Adjust perform the beginning again.
focus bias adjustment may not have been carried out prop-
erly. Adjust perform the beginning again.
– 18 –
6-11. Adjusting Points and Connecting Points
[BD (MD) BOARD]
[BD (MD) BOARD]
(Component side)
IC191
D101
[BD (MD) BOARD]
(Conductor side)
(IOP)
(I+5V)
RV101
RV102
(VC)
IC101
(TEO)
IC121
– 19 –
FM Stereo Separation Adjustment
Setting :
FM RF SSG
FM ANTENNA terminal (TM1)
set
Carrier frequency : 98MHz
Output level
Output level
: 1mV (60dB)
Modulation
Main (1kHz)
: 33.75kHz dev. (45%)
Sub (1kHz)
: 33.75kHz dev. (45%)
Pilot (19kHz)
: 7.5kHz dev.
(10%)
+
–
J601 (LINE OUT)
47k
Ω
level meter
Procedure :
Turn the set to 98MHz.
Turn the set to 98MHz.
FM stereo
VTVM
VTVM
signal generator
connection
reading (dB)
output channel
L-CH
L-CH
A
R-CH
L-CH
B
Adjust RV (FM STEREO
SEPARATION ADJUST-
MENT) for minimum read-
ing.
SEPARATION ADJUST-
MENT) for minimum read-
ing.
R-CH
R-CH
C
L-CH
R-CH
D
Adjust RV (FM STEREO
SEPARATION ADJUST-
MENT) for minimum read-
ing.
SEPARATION ADJUST-
MENT) for minimum read-
ing.
L-CH Stereo separation : A - B
R-CH Stereo separation : C - D
R-CH Stereo separation : C - D
The separations of both channels should be equal.
Adjustment Location : TB1 (TUNER board)
[TB1 TUNER BOARD]
(Conductor side )
RV (FM TUNED
LEVEL ADJUSTMENT)
LEVEL ADJUSTMENT)
RV (AM TUNED LEVEL ADJUSTMENT)
RV (FM STEREO SEPARATION ADJUSTMENT)
IC
IC
TUNER SECTION
As a front-end (TB1) is difficult to repair if faulty, replace it with
new one.
But AEP, UK, German, and Italian model are please note, however,
that the following adjustments are possible:
new one.
But AEP, UK, German, and Italian model are please note, however,
that the following adjustments are possible:
AM Section Adjustment
AM Tuned Indication Lighting Level Adjustment
AM Tuned Indication Lighting Level Adjustment
Band : AM
Setting :
Setting :
60 cm
AM ANTENNA
terminal (TM1)
terminal (TM1)
set
AM RF SSG
carrier frequency : 999kHz
Modulation : 400Hz 30%
Modulation : 400Hz 30%
loop antenna
loop antenna of
accessories
accessories
Procedure :
1. Set AM RF SSG output level to 81dB
1. Set AM RF SSG output level to 81dB
µ
so that the input level
becomes 55dB
µ
.
2. Tune the set to 999kHz .
3. Adjust RV(AM TUNED LEVEL ADJUSTMENT) so that the
3. Adjust RV(AM TUNED LEVEL ADJUSTMENT) so that the
TUNED light up.
Adjustment Location : TB1 (TUNER board)
FM Section Adjustment
FM Tuned Indication Lighting Level Adjustment
FM Tuned Indication Lighting Level Adjustment
Band : FW
Setting :
Setting :
FM RF SSG
FM ANTENNA terminal (TM1)
set
carrier frequency : 98MHz
Modulation
Modulation
: 1kHz,75kHz deviation
Procedure :
1. Supply a 17.8
1. Supply a 17.8
µ
V (25dB
µ
) 98MHz signal to the ANTENNA ter-
minal.
2. Tune the set to 98MHz.
3. Adjust RV(FM TUNED LEVEL ADJUSTMENT) so that the
3. Adjust RV(FM TUNED LEVEL ADJUSTMENT) so that the
TUNED light up.
Adjustment Location : TB1 (TUNER board)
– 20 –
CD SECTION
NOTE :
NOTE :
1. CD Block basically constructed to operate without adjustment.
Therefore, check each item in order given.
2. Use YEDS-18 disc (3-702-101-01) unless otherwise indicated.
3. Use the oscilloscope with more than 10M
3. Use the oscilloscope with more than 10M
Ω
impedance.
4. Clean an object lens by an applicator with neutral detergent when
the signal level is low than specified value with the following
checks.
checks.
Focus Bias Adjustment
This adjustment is to be done when the optical block is replaced.
Adjustment procedure :
+
–
BD (CD) board
TP (RF)
TP (VC)
oscilloscope
(DC range)
1. Connect oscilloscope to test point TP (VC) and TP (RF) on BD
(CD) board.
2. Connect TP ADJ (IC301 @• pin) to ground with lead wire on Main
board.
3. Turned power switch ON. (Stop mode)
4. Put disc (YEDS-18) in and press the
4. Put disc (YEDS-18) in and press the
^ button.
5. Press the
^ button (Tracking servo ON).
6. Adjust RV101 so that the oscilloscope waveform is as shown in
the figure below (eye pattern).
A good eye pattern means that the diamond shape ( ) in the center
of the waveform can be clearly distinguished.
A good eye pattern means that the diamond shape ( ) in the center
of the waveform can be clearly distinguished.
7. After adjustment,remove the lead wire connected in step 2.
r
RF signal reference waveform (eye pattern)
VOLT/DIV : 0.2V
TIME/DIV : 500ns
TIME/DIV : 500ns
1.3
±
0.3Vp-p
When observing the eye pattern, set the oscilloscope for AC range
and raise vertical sensitivity.
and raise vertical sensitivity.
Adjustment Location : BD (CD) board. (see page 13)
S-Curve Check
+
–
oscilloscope
TP (FEO)
BD (CD) board
TP (VC)
Procedure :
1. Connect oscilloscope to test point TP (VC) and TP (FEO) on BD
1. Connect oscilloscope to test point TP (VC) and TP (FEO) on BD
(CD) board.
2. Connect between test point TP (FOK) and GND by lead wire.
3. Turned Power switch on.
4. Put disc (YEDS-18) in and turned Power switch on again and
3. Turned Power switch on.
4. Put disc (YEDS-18) in and turned Power switch on again and
actuate the focus search. (actuate the focus search when disc table
is moving in and out.)
is moving in and out.)
5. Check the oscilloscope waveform (S-curve) is symmetrical be-
tween A and B. And confirm peak to peak level within
2.4 ± 0.7Vp-p.
2.4 ± 0.7Vp-p.
symmetry
within 2.4
±
0.7Vp-p
A
B
S-curve waveform
6. After check, remove the lead wire connected in step 2.
Note :
r
Try to measure several times to make sure that the ratio
of A : B or B : A is more than 10 : 7.
of A : B or B : A is more than 10 : 7.
r
Take sweep time as long as possible and light up the bright
ness to obtain best waveform.
ness to obtain best waveform.
Adjustment Location : BD (CD) board. (see page 13)
RF Level Check
+
–
oscilloscope
TP (RF)
BD (CD) board
TP (VC)
Procedure :
1. Connect oscilloscope to test point TP (VC) and TP (RF) on BD
1. Connect oscilloscope to test point TP (VC) and TP (RF) on BD
(CD) board.
2. Turned Power switch on.
3. Put disc (YEDS-18) in and press the
3. Put disc (YEDS-18) in and press the
^ button.
4. Confirm that oscilloscope waveform is clear and check RF signal
level is correct or not.
Note :
Clear RF signal waveform means that the shape “
◊
” can be clearly
distinguished at the center of the waveform.
r
RF signal waveform
VOLT/DIV : 200mV
TIME/DIV : 500ns
TIME/DIV : 500ns
level : 1.3
±
0.3Vp-p
Adjustment Location : BD (CD) board. (see page 13)
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