Service manual
33
VL-AX1U
(Wiring board diagram: Main Side B)
9. VF brightness adjustment
Test point TL8841(VG) Address VCR ADJ E0
Mode VCR AV input
Procedure 1) Input the signal of a 3-step waveform.
2) Set VCR ADJ ED to 00.
3) Adjust the waveform pedestal range of TL8841 to the specified adjustment value.
4) Return VCR ADJ ED to the initial value. (Initial value: 7A)
Adjustment 7.4Vp-p ± 0.1Vp-p
rating
Examples • During IC705 or IC8800 replacement.
Sig. center
7.4Vp-p 0.1Vp-p
GND
7. VF VCO adjustment
Test point TL8861(BLD) Address VCR ADJ E1
Mode VCR AV input
Procedure 1) Connect TL7801 to GND. (No signal)
2) Connect TL8861 to the frequency counter, and adjust the frequency to the specified adjustment value with the
VCR ADJ E1.
Adjustment 15.734 ± 0.1KHz
rating
Examples • During IC705 or IC8800 replacement.
8. VF COM-DC adjustment
Test point TL8840 Address VCR ADJ F6
Mode VCR AV input
Procedure 1) Input the signal of a 3-step waveform.
2) Read the DC voltage value of the output of TL8841 with the digital voltmeter. (VG
DC
)
3) Similarly rad the DC voltage value of the output of TL8840 with the digital voltmeter. (VCOM
DC
)
4) Adjust the value of (VCOM
DC
- VG
DC
) to the specified adjustment value.
Adjustment -0.15 ± 0.1V
rating
Examples • During IC705 or IC8800 replacement.
TL1475TL1478 TL1481TL1479
TL1431
TL239TL245TL244TL243TL242TL241TL235TL240
TL1420
R257
R244
TL233
TL234
TL4438
R255
TL201
TL202
TL4439
TL4437
R243
R242
R258
C205
TL236
R206
SC201
TL237
R204
TL238
R203
R207
R208
R201
R213
R202
C204
C2509
L2501
R235
R797
R796
SC701
R2506
C2507
R2504
C2508
R2502
R2501
C2506
C2505
TL2802
C2504
TL2801
C2502
C2503
SC2501
TL2800
C2553
Q2503
C2554
C2511
R2518
L2502
R2524
R2537
R2523
R2517
Q2508
Q2501
R2527 R2525
R2530 R2521
R1474
D2501 R2519 R2522
FB1471
R2529
R1477
C2520 R2520
R2528
R1473
C2517 C2518
R2526
R1475
D2504
TL1477
TL1480
R1472
SC1401
R2606
R1471
R2610
R2604
R1476
R2623
R2616
FB1472
R2617
R1470
R2615
R2605
C2552
C2551
R2810
Q2800
R2819
R2820
R2818
R2831
TL1908
TL2803
R2813
TL2804
R2824
R2822
R2823
R2825
C2808
TL2815
R2811
R2814
TL2816
TL2817
TL2812
TL2820
TL2833
SC2801
TL911
TL2834
TL1909
TL1913
TL2825
TL2819
TL2818
TL2814
TL2813
TL2811
TL5758
TL5760
TL8861
TL8855
TL783
TL8840TL8842TL8841TL8843
SC5704
R2833
TL5756
TL5768
TL4436
TL5759
TL5761
TL417
R2815
C2805
R2582
R2812
R2832
Q2510
D2801
R2583 R2584
R2588 R2585
C2807
C2548
R2592
R2581
R2589
R2594
C2542
R2586
R2593
IC2507
C2546
R2590
R2587
R2512
R2516
C2549
Q504
C2544
R2511
C2516
R2514
R2509
R537
R517
C2512 R2507
C514
IC2502
R2515 R2508
C2515
TL5789
R2534
C2513
R2513
TL5790
Q2507
R2510
TL5788
TL5786
R2533
Q2504
Q2502
R521
R522
TL5778
TL5752
R523
R2532
C2555
C2556
R2538
C2530
C2531
TL4405
TL7801
TL4403
R2503
IC2501
TL4404
R2505
C2501 C2510
C202
C501
L501
TL912
C5701
C5703
C5704
C5702
FB203
C208
C210
C239
C222
R205
C224
R209
C231
C223
TL7823
C226
IC201
C227 C228 C240 C235
TL4441
TL908
C209
C211
C212
C215
FB204
R251
L204
C203
C213
IC202
C230
FB201
R526
C507
R509
TL7800
TL4440
IC501
R514 C504 R531
TL5767
C516
C515
C513
R518
R516
R519
FL501
R520
C4702
TL5776
IC503
TL3321
TL416
TL403
C508
TL3322
C404
TL3320
R442
R407
R411
Q1947
C452
R412
C451
C407
R443
C405
R1992
R406
R446
R416
IC
4
S
R1720
R1721
TL5770
C512
R535
C502
C511
R536
C503
R505
R504
C509
R532
R533
TL5781
TL5780
C701
R506
R780
D1900
R1911
Q1920
R1912
C237
C1994
R1934
Q
R1935
Q1938
C1921
R1940
R1943
C238
Q1913
TL8842(VR)
VF sub-brightness R/B
TL8843(VB)
VF sub-brightness R/B
TL8841(VG)
VF COM-DC
VF brightness
VF contrast
VFγ1
VF sub-brightness R/B
TL8861(BLD)
VF VCO
TL8840
VF COM-DC
TL7801
VF VCO