Sharp VL-Z700S-T Service Manual page 32

VL-Z700S-T
VL-Z800S-S/E-S/E-T/Z900H-S
VL-Z950S-S/E-A/E-S/E-T/E-W
3. Adjustment of VF_DAC full scale (Main PWB)
Measurement point
Procedure
Adjustment rating
Examples
4. Adjustment of VF_WB (Main PWB)
Measurement point
Address
Procedure
Adjustment rating
Examples
TL7824(VF_G_OUT)
1) Set the data values at addresses 587 (GRYLEV)/58C (γ PEAK)/5EB (TESTSW2) and 5E6 (OSDSW)
to FF/80/77 and 00, respectively. (The LED shows nothing.)
2) Set the data values at addresses 59F (CLAMP)/58D (PEDESTAL) and 5B7 (VCLK3 INV) to 00/80 and
48, respectively.
3) Connect the digital voltmeter to TL7824 (VF_G_OUT) and measure the DC voltage.
* The measured voltage is (DA_VF-G).
4) Set the data values at addresses 59F (CLAMP) and 58D (PEDESTAL) to 80 and 00, respectively.
5) At address 59D (VF_DAC_G), adjust the DC voltage to the adjustment rating.
6) Reset the data at addresses 587 (GRYLEV)/58C (γ PEAK)/58D (PEDESTAL)/59F (CLAMP)/5B7
(VCLK3 INV)/5E6 (OSDSW) and 5EB (TESTSW2) to their original values.
(Initial values: 40/C5/38/28/90/28 and 7F)
DA_VF-G +0.39V ± 10mV
· Replacement of IC705, IC4401
TL8804(VF_VG), TL8805(VF_VR), TL8806(VF_VB)
VCR ADJ 58E, 590
1) Set the data values at addresses 587 (GRYLEV) and 5E6 (OSDSW) to 80 and 70, respectively.
2) Connect the oscilloscope to TL8804 (VF_VG) and TL8805 (VF_VR), and at address 58E (VF_WB-
R), adjust the amplitude to the adjustment rating.
3) Connect the oscilloscope to TL8804 (VF_VG) and TL8806 (VF_VB), and at address 590
(VF_WB_B), adjust the amplitude to the adjustment rating.
0mV ± 40mV, 0.1mV ± 40mV
· Replacement of IC705, IC4401, IC8801
Address VCR ADJ 59D
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