SECTION 5
CIRCUIT ADJUSTMENTS
– 46 –
5-4. SUB-HUE AND SUB-COLOR ADJUSTMENT
(SHUE, SCOL)
1. Receive the color-bar signal.
2. PICTURE : maximum
COLOR : minimum
BRIGHTNESS : minimum
3. Set to service mode.
4. Connect an oscilloscope between 7 pin of CN004 (A Board)
connecter and ground.
5. Select “ SHUE ” and “ SCOL ”, and adjust them to have
VB1 = VB4 and VB2 = VB3 in the waveform levels.
6. Raise SCOL data 1 steps higher.
7. Write the data into memory.
MUTING n ENTER
5-1. RF AGC
1. Input a color-bar signal.
2. Adjust AGC VR of TU1101 so that snow noise, and
crossmodulation disapper from the picture.
3. Verify picture quality on each channel.
5-2. BER DISPLAY ADJUSTMENT (DISP)
1. Receive the cross-hatch signal.
2. Set to Service mode.
3. Select “ DISP ”, and adjust so that the blank spaces on the
both sides of picture bar become equal.
4. Write the data into memory.
MUTING n ENTER
ABA=B
Fig. 5-1
5-3. SUB CONTRAST ADJUSTMENT (SCON)
1. Receive the color-bar signal.
2. PICTURE : maximum
COLOR : minimum
BRIGHTNESS : minimum
RON---1 GON---0 BON---0
3. Set to service mode.
4. Connect an oscilloscope between 6 pin of CN004 (A board)
and ground.
5. Select “ SCON ”, and adjust so that the wave from level is
1.65±0.05Vp-p.
6. Write the data into memory.
MUTING n ENTER
5-5. P IN P POSITION ADJUSTMENT (PIPH, PIPV)
1. Receive the monoscope signal.
2. Set to P IN P ( ) mode, and to Service mode.
3. Check the SUB PICTURE position.
4. Select “ PIPH ” and “ PIPV ” and adjust H/V position to the
center level.
5. Write the data into memory.
MUTING n ENTER
H
V
H : 7.00 ± 0.25sq
V : 5.25 ± 0.25sq
Fig. 5-4
White
1.65
±
0.05Vp-p
Black
Fig. 5-2
VB1 VB2 VB3 VB4
Fig. 5-3