Ⅱ
. Alignment contents
1. Mains Supply check:
Turn on TV and set volume, contrast, brightness and color to nominal, apply a RF signal modulated with
a white pattern. Check the voltage across C835, it should match the below table or check the mains supply
building block.
Model
CRT
Mains supply (V)
14DN2NYD 44-140FLP-IR1A
108
±
3
2. AFT adjustment:
1)
Cut off the RF signal and input a 45.75MHz (for NTSC set) color bar signal to the IF pin of tuner
(pin11).
2)
Adjust T201 until the voltage at pin 48 of IC201 is 4.62 +/- 0.2V and the color bar picture on screen
keep stable.
3)
Enter D-mode page 9 and select “SFVCO”, press “VOL+” to shift the data to “01”. Then Auto AFT
Adjustment start and “wait” is displayed on screen. SFVCO will return to “00” and “ok” is displayed on
screen when the adjustment is accomplished.
4)
If “err” is display on screen, repeat the step 2 and 3.
3. RF AGC adjustment
1) Via a 50 OHM coaxial cable terminated with a RC(50 OHM, 10 nF) network Illustrated as below, input
8-scale gray signal (100% video modulation, sound carrier off, 105dBuV/178mVrms) to the IF pin of
tuner (pin11);
2) Detect the voltage Urf at the AGC pin of tuner (pin1);
3) Adjust RFAGC data in D-mode page 9, until Urf=3.3V+0.5V/-1.0V
.
4) Test three units according to 1)
，
2)
，
3) steps, and record the values of AGC in three units. Take the
average value as benchmark.
Remarks:
1)
Comparing test is necessary due to different probe of Oscilloscope and different Test Circuit.
2)
AGC voltage value should be tested afresh, due to the type/supplier of Tuner or Saw filter
changed, or other related components changed.
10nF
output
input
50 O H M
TTE Overseas Support Department
Summary of Contents for 14DN2NYD
Page 41: ...5 Block Diagram TTE Overseas Support Department...
Page 42: ...6 Schematic Diagram...
Page 43: ...7 PCB Layout...
Page 44: ......
Page 45: ...8 Explode View Diagram...
