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3-7.COLOR PHASE (TINT) ALIGNMENT (RV308)
1. Receive the color bar signal from the signal generator.
2. Observe the waveform across JL422(VB) and JL407(GND).
3. Adjust RV308 (TINT) so that the waveform level resembles
2. Observe the waveform across JL422(VB) and JL407(GND).
3. Adjust RV308 (TINT) so that the waveform level resembles
that of Fig. 3-7.
3-6.CONTRAST ALIGNMENT (RV301)
1. Receive the stepped waveform signal in 10 steps.
2. Observe the waveform across JL421(VG) and JL407(GND).
3. Align RV301 (CONT) so that 100IRE section matches the
2. Observe the waveform across JL421(VG) and JL407(GND).
3. Align RV301 (CONT) so that 100IRE section matches the
standard below. (Fig. 3-6)
3-5.V COM ALIGNMENT (RV302, RV306)
1. Adjust BRT VR (RV901) to1.740
±
0.005VDC, between
JL301(BRT) and JL307 (A.GND).
2. Observe the waveform across JL411 (V COM) and
JL407(GND).
3. Adjust RV302 (COM AMP) and RV306 (V COM DC) so that
the waveform resembles that in Fig. 3-5.
Note : The voltage at pin 37 (COMMON AMP) of IC302 shall
be a minimum of 1.8V.
3-3.RF. AGC ALIGNMENT (RV201)
1. Set S601 to VHF position and receive a VHF color bar signal
issued from a signal generator.
2. Adjust RV201 and align the screen for the optimal point so
that the snow noise disappears.
3-4.CHANNEL DISPLAY POSITION ALIGNMENT
(RV001, RV002, RV003, RV004)
1. Set S601 to VHF position, a potentiometer (47k
Ω±
15k
Ω
)
across JL06(CS) and JL09 (+5.0 V) as shown in Fig. 2-6 and
short the points JL04(CH CAL) and JL01 (D.GND).
short the points JL04(CH CAL) and JL01 (D.GND).
2. Receive channel 2 and align the channel display positions with
RV002(VP).
3. Receive channel 13 and align the display bar with RV004(VA).
4. Align while performing tracking to mutual interference in the
4. Align while performing tracking to mutual interference in the
above steps 2 and 3.
5. Receive channels 3 & 4 and confirm that the display bar is
within the standards.
6. Set S601 to UHF.
7. Receive channel 14 and align the display position with
7. Receive channel 14 and align the display position with
RV001(UP).
8. Receive channel 69 and confirm that the display bar is within
the standards. If not within standards, align with RV003 so it
is within standards.
is within standards.
Once again receive channel 14 and confirm that the display bar
is within the standards.
Note
: Use caution since shifting channel 69 will also
cause channel 14 to shift.
9. Remove the potentiometer (47k
9. Remove the potentiometer (47k
Ω
+15k
Ω
) you connected be-
tween JL06(CS) and JL09(+5.0V). Also remove the short you
connected between points JL04 (CH CAL)and JL01(D.GND).
connected between points JL04 (CH CAL)and JL01(D.GND).
3-2.AFT FINE ADJUSTMENT (T201)
1. Connect a 1 kilohm resistor between JL09 (+5.0V) and JL13
(RF AGC).
Note
: Perform this adjustment as the last step in the
process since drift may occur due to aging.
2. Switch the sweep signal to CW.
2. Switch the sweep signal to CW.
fo= 45.75 MHz
±
5 kHz, -30
±
5dBm
Apply the above signal between JL12 (IF) and JL14 (IF GND)
and then make a fine adjustment of T201 so that the level be-
and then make a fine adjustment of T201 so that the level be-
tween JL02 (AFT) and JL01 (D.GND) reaches2.2V
±
0.4VDC.
3. Remove the 1 kilohm resistor connected between JL09 (+5.0V)
and JL13 (RF AGC).
Align so the portion is parallel and linear.
10thstep
(100IRE)
(100IRE)
3.0V
±
0.1Vp-p
5.0V
±
0.1Vp-p
-1.4V
±
0.1Vp-p
0V
Fig. 3-5
Fig. 3-6
Fig. 3-7
Fig. 3-4
Display bar
Channel No.
6
*Channel No. and display
bar are to be in line.
bar are to be in line.
< B BOARD ALIGNMENT >
RV302
RV308
RV301
RV306
- B board -
(Component side)
(Component side)
JL06 (CS)
JL09(+5.0V)
15k
Ω
VR(47k
Ω
)
MEMO
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