— 7 —
APC DET ADJUSTMENT
Note: APC DET must be adjusted after IC101 (Signal
Processor), IC802 (EEPROM) or T151 (PLL VCO Coil)
is replaced.
1. Disconnect the antenna terminal and the AC power cord
(120V AC line).
2. Connect vol lead to TP113 on main board and
– lead to main board ground.
3. While pressing the MENU key, reconnect the AC power
cord. The Service Menu display will now appear.
4. Select No. 002 IAS (IF AGC Switch) with
▲
or
▼
key. and
adjust the data to 1 with + or – key.
5. Select No. 005 ADA (APC Det. Adjust.) with
▲
or
▼
key.
and adjust the data with + or – key for 3.8 ± 1.0 VDC.
Voltage change in the ADA BUS data adjustments is shown
in Figure 6.
6. Disconnect voltmeter from chassis.
PLL TUNING ADJUSTMENT
Note: APC DET Adjustment must be completed before
attempting PLL Tuning Adjustment.
1. Disconnect the antenna terminal and the AC power cord
(120V AC line).
2. Connect vol lead to TP113 on main board and
– lead to main board ground.
3. While pressing the MENU key, reconnect the AC power
cord. The Service Menu display will now appear.
4. Select No. 002 IAS (IF AGC Switch) with
▲
or
▼
key.and
adjust the data to 0 with + or – key.
5. Select No. 004 PT (PLL Tuning) with
▲
or
▼
key.
6. Connect the antenna terminal and select a good quality
active color channel in your area, using keys 0 ~ 9 on the
remote control transmitter.
7. Adjust the data with + or – key for 3.8 ± 1.0 VDC. Voltage
change in the PT BUS data adjustments is shown in Figure
7.
8. Disconnect voltmeter from chassis.
Select every active channel with 0 ~ 9 keys and the scanning
keys, and check to be sure the AFT is operating properly.
VIDEO LEVEL ADJUSTMENT
1. Connect a color-bar generator to the antenna terminal.
2. Switch the generator to a white field (100 IRE).
3. Connect oscill lead to terminal TP16A on main
board and – lead to main board ground.
4. Set the picture controls to the Auto levels.
5. Confirm voltage reading of 2.0 ± 0.2 Vp-p. If voltage is
within this range, Skip to Step 10. If voltage is out of this
range, go to step 6.
6. Turn off the receiver and disconnect the AC power cord
(120V AC line).
7. While pressing the MENU key, reconnect the AC power
cord. The Service Menu display will now appear.
8. Select No. 016 VL (Video Level) with
▲
or
▼
key.
9. Adjust the data with + or –key for 2.0 ± 0.2 Vp-p. To turn off
the Service Menu display, press the MENU key.
10. Disconnect voltmeter from chassis.
RF-AGC ADJUSTMENT
1. Tune receiver to strongest VHF station in your area.
2. Set contrast and brightness controls for maximum.
3. Turn off the receiver and disconnect the AC power cord
(120V AC line).
4. While pressing the MENU key, reconnect the AC power
cord. The Service Menu display will now appear.
5. Select No. 003 RAD (RF-AGC Delay) with
▲
or
▼
key.
6. Adjust the data with + or – key in the direction which
causes snow to appear; then in the opposite direction until
the snow just disappears.
7 . To turn off the Service Menu display, press the MENU key.
BRIGHTNESS LEVEL ADJUSTMENT
Note: Grayscale, RF-AGC, Video Level and High Voltage Check
must be adjusted before attempting Brightness Level
Adjustment.
1. Connect a color-bar generator to the antenna terminals.
2. Switch the generator to the crosshatch pattern.
3. Set the picture controls to the Auto levels.
4. Connect voltmeter (high impedance) + lead to terminal
TP51 and – lead to terminal TP50 on main board. Set
voltmeter for 1.5V ~ 3V range.
5. Turn off the receiver and disconnect the AC power cord
(120V AC line).
6. While pressing the MENU key, reconnect the AC power
cord. The Service Menu display will now appear.
7. Select No. 025 SB (Sub Brightness) with
▲
or
▼
key.
8. Adjust the data with + or – key for 600mVDC.
9. Press the MENU key to turn off the Service Menu display.
10. Check brightness level on every active channel, readjust
(repeat steps 5 ~ 9) if necessary.
Note: Do not set to excessive brightness level, otherwise the
contrast level will be suppressed.
63 (steps)
ADA BUS DATA
VO
LTA
G
E
TP113
3.8V
Figure 6. Voltage Change in ADA BUS data Adjustments
Figure 7. Voltage Change in PT BUS data Adjustments
127 (steps)
PT BUS DATA
VO
LTA
G
E
TP113
3.8V
Summary of Contents for DS13310, DS19310
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