Sharp SX80J9, Service Manual

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12-1 12-2
SX80J9
SECAM CHROMA ADJUSTMENT
1. BELL FILTER fo ADJUSTMENT
(I
2
C bus adjustment)
1. Receive the OI-5CH "SECAM COLOUR BAR" sig-
nal.
2. Call the bell filter fo adjustment mode.
3. Connect the oscilloscope to pin (21)(TP901) of
IC901.
• Range
: 10mV/div. (AC)
• Sweep time : 20µsec/div.
4. Adjust the bell filter data to have a waveform, the
shape of whitch closest to the Fig.11.
2. SECAM BLACK LEVEL (R-Y/B-Y) ADJUSTMENT
(I
2
C bus adjustment)
1. Receive the OI-5CH "SECAM COLOUR BAR" sig-
nal.
2. Call the SECAM R-Y adjustment mode.
3. Connect the oscilloscope to pin (11)(R-Y
OUT,TP801) of IC901.
• Range
: 10mV/div.
• Sweep time : 20µsec/div.
(Use a 10:1 probe.)
4. Adjust the R-Y data so that the offset between the
no-signal and the signal line be minimum.See
Fig.12.
5. Call the SECAM B-Y adjustment mode.
6. Reconnect the oscilloscope to pin (10) (B-Y OUT,
TP802) of IC901. Take the same conditions as in
step 3 above.
7. Adjust the B-Y data so that the offset between the
no-signal and the signal line be minimum.See
Fig.12.
To be at the same levbel
OFF
SET
OFF
SET
A/V INPUT AND OUTPUT CHECK
1. AUDIO/VIDEO OUTPUT CHECK
1. Receive the E-12CH "PAL COLOUR BAR" signal (100% white colour bar, sound 400Hz, 100% mod.).
2. Terminate the video output with a 75-ohm impedance. Make sure the output is as specified (1.0Vp-p ± 3dB).
3. Terminate the audio output with a 10k-ohm impedance. Make sure the output is as specified (1.76Vp-p ±
3dB).
2. AUDIO/VIDEO INPUT CHECK, S-TERMINAL INPUT CHECK
1. Using the TV/VIDEO key on the remote controller, make sure that the modes change in order of TV, AV1, AV2,
AV3 and TV again and that the video and audio outputs are according to the input and output terminals for
each mode.
2. In the AV1 mode, connect the connector to the S-VIDEO input terminal. Make sure the AV mode changes to
the S-VIDEO mode, that the unit functions well, and that "AV1-S" appears on the screen.
3. AV3 AUTOMATIC SELECT CHECK
1. Using the remote controller, receive a TV broadcast signal.
2. Feed the signal to the AV3 VIDEO input terminal. Make sure the AV3 mode shows up automatically.
* Setting:AUTO SELECT to be turn on.
PROTECTOR PERFORMANCE CHECK
1. BEAM PROTECTOR
1. Receive the E-5CH "MONOSCOPE PATTERN" signal.
2. Set the contrast control to maximmum.
3. Set the brightness control to maximum.
4. Make a short-circuit between the collector and emitter of Q853 and make sure that the protector is activated
and the stand-by mode is called.
2. HIGH-VOLTAGE PROTECTOR
1. Receive the E-5CH "MONOSCOPE PATTERN" signal.
2. Connect the bias box to the cathode (R1625 side) of D1607.
3. Adjust the bias box voltage to 16V and make sure that the protector is not activated.
• Reference : Usual activate voltage is 19.7V.
4. Boost the bias box voltage to 24V and make sure that the protector is activated.
3. OTHER PROTECTORS
1. In checking the performance of other protectors – for example, the one against shorting of smoothing electolytic
capacitor of + B line ( pay attention not to damage or deteriorate element ).
Fig. 11
Fig. 12