18
HCD-DX70
FM Tuned Level Adjustment
Procedure:
1.
Supply a 28 dB 98 MHz signal from the ANTENNA terminal.
2.
Tune the set to 98 MHz.
3.
Adjust RV611 to the point (moment) when the TUNED
indicator will change from going off to going on.
Adjustment Location:
MAIN board
Null Adjustment
Procedure:
1.
Supply a 60 dB 98 MHz signal from the ANTENNA terminal.
2.
Tune the set to 98 MHz.
3.
Measure voltage between pin 21 of IC 601. Adjust T11 ubtil
the voltage becomes 0 V.
Adjustment Location:
MAIN board
Adjustment Location
[MAIN BOARD] Component side
FM RF SSG
75
Ω
coaxial
Carrier frequency : 98 MHz
Modulation : AUDIO 1 kHz, 75 kHz
deviation (100%)
Output level : 28 dB (at 75 W open)
FM ANTENNA terminal
(TM1)
set
FM RF SSG
75
Ω
coaxial
Carrier frequency : 98 MHz
Modulation : AUDIO 1 kHz, 75 kHz
deviation (100%)
Output level : 60 dB (at 75 W open)
FM ANTENNA terminal
(TM1)
set
CD SECTION
Note :
1. CD Block is basically designed to operate without adjustment.
Therefore, check each item in order given.
2. Use LUV-P01 (4-999-032-01) unless otherwise indicated.
3. Use an oscilloscope with more than 10M
Ω
impedance.
4. Clean the object lens by an applicator with neutral detergent
when the signal level is low than specified value with the
following checks.
S-Curve Check
Procedure :
1. Connect oscilloscope to TP (FEO).
2. Connect between TP (FEI) and TP (DVC ( 1.65 V) by lead
wire.
3. Turn Power switch on.
4. Load a disc (LUV-P01) and actuate the focus search. (In
consequence of open and close the disc tray, actuate the focus
search)
5. Confirm that the oscilloscope waveform (S-curve) is
symmetrical between A and B. And confirm peak to peak level
within 2 ±0.5 Vp-p.
6. After check, remove the lead wire connected in step 2.
Note :
• Try to measure several times to make sure than the ratio
of A : B or B : A is more than 10 : 7.
• Take sweep time as long as possible and light up the
brightness to obtain best waveform.
RF Level Check
Procedure :
1. Connect oscilloscope to TP (RFDC) and (RFAC).
2. Turned Power switch on.
3. Load a disc (LUV-P01) and playback.
4. Confirm that oscilloscope waveform is clear and check RF signal
level is correct or not.
BD board
Oscilloscope
TP(FEO)
TP(DVC)
symmetry
S-curve waveform
within 2
±
0.5Vp-p
A
B
TP(RF)
TP(DVC)
BD board
oscilloscope
RV354
CN303
CN301
CN304
RV304
RV301
RV352
RV302
RV353
RV303
RV351
RV11
T11
FM TUNED LEVEL
NULL
1
3
Содержание HCD-DX70
Страница 28: ...HCD DX70 28 28 6 7 SCHEMATIC DIAGRAM MAIN 2 4 SECTION Page 24 Page 41 Page 29 Page 27 Page 30 ...
Страница 33: ...33 33 HCD DX70 6 13 SCHEMATIC DIAGRAM POWER AMP SECTION Page 43 Page 43 Page 30 Page 30 ...
Страница 37: ...37 37 HCD DX70 6 17 SCHEMATIC DIAGRAM SWITCH SECTION Page 35 Page 35 ...
Страница 39: ...39 39 HCD DX70 6 19 SCHEMATIC DIAGRAM LEAF SW SECTION E Page 30 4 4 ...
Страница 41: ...41 41 HCD DX70 6 21 SCHEMATIC DIAGRAMS DRIVER SECTION See page 50 for IC Block Diagrams IC B D B Page 28 2 4 ...
Страница 43: ...43 43 HCD DX70 6 23 SCHEMATIC DIAGRAM TRANS SECTION H Page 33 Page 33 ...