Electrical Checks - Sony HCD-DH7BT - Dvd Receiver For Cmtdh7bt Micro System Service Manual

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TUNER SECTION
FM TUNE LEVEL CHECK
signal
generator
set
Procedure:
1. Turn on the set.
2. Input the following signal from signal generator to FM antenna
input directly.
Carrier frequency: A = 87.5 MHz, B = 98 MHz, C = 108 MHz
Deviation : 75 kHz
Modulation : 1 kHz
ANT input : 35 dBu (EMF)
Note: Use 75 ohm coaxial cable to connect signal generator and the set.
You cannot use video cable for checking.
Use signal generator whose output impedance is 75 ohm.
3. Set to FM tuner function and tune A, B and C signals.
4. Confirm "TUNED" is lit on the display for A, B and C signals.
When the selected station signal is received in good condition,
"TUNED" is displayed.
DVD SECTION
T E
L 3
TEST DISC LIST
Be sure to use the DVD disc that matches the signal standards of
your region.
CD
YEDS-18 (Part No.: 3-702-101-01)
PATD-012 (Part No.: 4-225-203-01)
DVD SL (Single Layer)
HLX-503 (NTSC) (Part No.: J-6090-069-A)
HLX-504 (NTSC) (Part No.: J-6090-088-A)
HLX-506 (PAL) (Part No.: J-6090-077-A)
DVD DL (Dual Layer)
HLX-501 (NTSC) (Part No.: J-6090-071-A)
HLX-505 (NTSC) (Part No.: J-6090-089-A)
HLX-507 (PAL) (Part No.: J-6090-078-A)
RFMON LEVEL CHECK
Connection :
oscilloscope
DMB15 board
CN105 pin 6 (RFMON)
CN105 pin 3 (GND)
Procedure :
1. Connect an oscilloscope to CN105 pin 6 (RFMON) and
CN105 pin 3 (GND) on the DMB15 board.
2. Press the button to turn on the system.
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3. Insert the test disc (refer to "TEST DISC LIST") and press
the button to playback.
DVD N
4. Confirm that oscilloscope waveform is clear and check
RFMON signal level is correct or not.
Note: A clear RFMON signal waveform means that the shape " " can be
clearly distinguished at the center of the waveform.
HCD-DH3/DH5BT/DH7BT
SECTION 5

ELECTRICAL CHECKS

5
Connecting Location:
– DMB15 Board (Side A) –
CN105
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IC201
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VIDEO SECTION
VIDEO LEVEL CHECK
Purpose :
This adjustment is made to satisfy the NTSC standard, and if not
adjusted correctly, the brightness will be too large or small.
75
set
VIDEO board
VIDEO OUT jack (J502)
Procedure :
1. Connect an oscilloscope to VIDOE OUT jack (J502) on the
+
VIDEO board.
–
2. Press the button to turn on the system.
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3. Insert the test disc (refer to "TEST DISC LIST") and press
the button to playback.
DVD N
4. Confirm the video signal level is 1.00
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(WHITE 100%)
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VOLT/DIV: 200 mV
TIME/DIV: 500 ns
level:
0.58 1.23 Vp-p
(DVD-SL)
0.57 1.1 Vp-p
(CD)
IC102
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Oscilloscope
0.07 Vp-p.
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1.00 0.07 Vp-p
.
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HCD-DH3/DH5BT/DH7BT
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