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Alignment and Adjustments

4. Alignment and Adjustments
4-1 Service Mode Adjustments
4-1-1 Service Mode Menus
Since there are no VRs in the K15A chassis, all adjustments after parts replacement must be done in the Service Mode. Service Mode adjustments are necessary when either the EEPROM (IC902) or the CRT is replaced.

4-1-2 Entering the Service Mode
Press the following transmitter keys while in STAND-BY mode: MUTE-->1-->8-->2-->POWER "Factory Mode Menu" is displayed ADJUSTMENT PATTERN OPTION RESET <---selected (violet)

Change the data with "Volume +, - " keys. VCO 71

Enter Service Mode using the Volume +,- keys. Service Mode Menu: AGC VCO SBT SCT SCR STT GG BG XX XX XX XX XX XXX XXX XXX RC XXX GC XXX BC XX VA XX VS XX HS XX SS XX SVC : MUTE

Return to the Service mode by pressing MENU. AGC VCO SBT SCT SCR STT GG BG XX XX XX XX XX XXX XXX XXX XXX RC XXX GC XX BC VA XX VS XX HS XX SS XX SVC : MUTE

Select a mode to be adjusted, using the channel down key. Example: VCO. AGC VCO SBT SCT SCR STT GG BG XX XX XX XX XX XXX XXX XXX RC XXX GC XXX BC XX VA XX VS XX HS XX SS XX SVC : MUTE

Return to the Factory mode via the MENU key. ADJUSTMENT PATTERN OPTION RESET Press POWER to enter the Stand-by mode.

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Alignment and Adjustments

4-1-3 Adjustment in Option Mode
This adjustment is necessary whenever the EEPROM is replaced. Input data (as marked on the back cabinet). ADJUSTMENT PATTERN OPTION RESET Select "SET OPTION" by pressing the Channel w key twice. ADJUSTMENT PATTERN OPTION RESET Press the Volume +, - keys to enter the set Option mode. BYTE 0 : 0 0 Press MENU to go back to the factory mode. ADJUSTMENT PATTERN OPTION RESET

4-1-4 Service Mode Adjustments

ADJUSTMENT PATTERN OPTION RESET 1. The Pattern Adjustment is done only in the factory. Do not attempt to readjust it. 2. Refer to 4-2 for other adjustments. 3. Set OPTION data.

4-1-5 Service Mode Adjustment Ratings
No Item Function Range 0~63 0~127 0~63 0~27 0~27 0~255 0~255 0~255 Initalized MICOM Data 50 63 48 13 7 0 0 0

1 AGC RF AGC Adjustment 2 VCO PIF VCO Adjustment 3 SCT SUB-CONTRAST Adjustment 4 SCR SUB-COLOR Adjustment 5 STT SUB-TINT Adjustment 6 RC 7 GC RED-CUT OFF Adjustment GREEN-CUT OFF Adjustment BLUE-CUT OFF Adjustment

Select RESET with channel ADJUSTMENT PATTERN OPTION RESET

w key.

8 BC

9 SVC Input a Horiz line pattern 10 GG 11 BG GREEN-GAIN Adjustment BLUE-GAIN Adjustment 0~255 0~255 0~63 0~63 0 0~31 0~31 127 127 31 39 0 15 4

12 SBT SUB-BRIGHTNESS Adjustment 13 VA VERTICAL SIZE Adjustment VERTICAL CENTER Adjustment HORIZONTAL Phase Adjustment SUB-SHARPNESS Adjustment

Press volume + key. POWER OFF

14 VS 15 HS 16 SS

Note : The initial MICOM data values take effect when IC902 is replaced.

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Alignment and Adjustments

4-2 Alignment and Adjustment
4-2-1 General Alignment Instructions
1. Usually, a color TV needs only slight touch-up adjustment upon installation. Check the basic characteristics such as picture height, focus and a horizontal and vertical sync. 2. Observe the picture and check for good back and white details. There should be no objectionable color shading: If color shading is present, demagnetize the receiver. If color shading persists, perform purity and convergence adjustments described below. 3. To protect against shock hazard, use an isolation transformer.

4-2-5 IC902 Replacement
1. When IC902 is replaced, all values are reset to "Initialized MICOM Data" and readjustment is necessary. 2. Press the POWER button 10 seconds after plug-in. 3. To enter the Service Mode, refer to Fig. 4-1 (Service Mode Adjustment).

4-2-6 PIF VCO Adjustment
1. Use a Pattern Generator or an off-air signal. 2. Open pin 11 of Micom (IC901) or one side of lead pin for R237. 3. Adjust VCO in the service mode to set IC101 Pin 44 (AFT) to 2.5V ± 0.4V. 4. Connect the opened site.

4-2-2 Power Supply Check
Check the following: A: Power plug is connected; "Stand-by" mode B: Power On when "Power ON" button is pressed C: Power On by FBT Each supply is marked on its lead-in wire. ( )

4-2-3 Focus Adjustment
Adjust the focus control on the FBT for well defined scanning lines.

4-2-7 RF-AGC Adjustment
1. 2. 3. 4. Input a PHILLIPS pattern. Set the input signal to 60 dB. Enter into the AGC in the service mode. Adjust AGC until color bar noise disappears.

4-2-4 Fail Safe Circuit Check (FS) (OPTION)
1. The failsafe check must be the final step in servicing. 2. Turn the power switch ON and adjust customer controls for normal operation. 3. Temporarily short pin X to pin R on the main board (RX06, RX04) with a jumper wire. Raster will disappear. 4. The TV must remain in this state even after removing the jumper wire. This shows that the failsafe circuit is working properly. 5. To recover picture and sound, temporarily turn off the TV and allow the failsafe circuit more than 30 seconds to reset. Then switch power ON to produce normal picture and sound.

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Alignment and Adjustments

4-2-8 Sub-Contrast Adjustment
1. Input a gray scale pattern. Use a pattern generator (PM5518). 2. 3. 4. Short D208 to switch off the ABL feed-back. Check CN201 R-OUT with an oscilloscope. Set RC, BC, GC data to 0 in the Service Mode.

4-2-10 Sub-Color Adjustment
1. Do sub-color adjustment after the SubContrast and Sub-Tint adjustments. 2. D208 should still be shorted. The ABL should still be switched OFF. 3. Input a color bar pattern. Use a pattern generator (PM5518). 4. Check CN201 R-OUT (use an oscilloscope). 5. Ensure that the RC, GC and BC data are 0. BG are 140 and GG should be 90. 6. Adjust SCR to 2.4 ± 0.1Vp-p (black and red levels).
+ 2.5V_ 0.1Vpp

5. Adjust SCT to 2.40 ± 0.1Vp-p

7. Remove the short across D208 and restore ABL.

6. Remove the short across D208 and restore ABL.

+ 2.4V _ 0.1Vpp

4-2-9 Sub-Tint Adjustment
1. 2. Input a rainbow pattern. Check CN201 B-OUT with an oscilloscope.

3. Adjust STT in the service mode until the 6th peak is the highest and the 5th and 7th peaks have equal heights.

3 1 2

4

5

6 7 8 9 10

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Alignment and Adjustments

4-2-11 White Balance Adjustment
4-2-11 (A) LOW-LIGHT ADJUSTMENTS
1. Input either a lion head or "pure white" color pattern. 2. Operate the receiver for 30 minutes. 3. Check the data in the service mode: RC, GC, BC are 0 and SB is 16; Steps BG are 90 and GG are 140. 4. Enter the horizontal line mode by pressing the MUTE key. 5. Adjust the screen VR on the FBT until a dim colored line (red,green or blue) appears on the screen. 6. After pressing the MUTE key, go to RC,BC or GC with channel , w keys. After putting a dim colored line (red, green or blue) in the horizontal line with MUTE key, adjust color with volume ,w keys. 7. Exit the horizontal line via the MUTE key.

4-2-13 Vertical Size Adjustment
1. Input a lion head pattern. 2. After the vertical center adjustment, enter into the service mode. 3. Adjust VA so that the each top and bottom of the screen is 4.0. If the top and bottom values are different, adjust VA so that the sum of the two values is 8.0.

4-2-14 Horizontal Size Adjustment
1. Receive a lion head pattern. 2. Enter into the service mode. 3. Adjust HS to symmetrized right and left.

4-2-11 (B) HIGH-LIGHT ADJUSTMENTS
1. Input a high-light pattern 2. Adjust GG,BG in the Service Mode. 3. Recheck in low light.

4-2-12 Sub-Brightness Adjustment
1. Input a Toshiba pattern. 2. Warm up the receiver for 10 minutes. 3. Enter the Service Mode and set SB to the point where the 5th point is brighter in the gray scale.

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w

4-2-15 When CRT Is Replaced
Do the following adjustments after the basic purity and convergence adjustments. 1. White Balance 2. Sub-brightness 3. Vertical Size 4. Horizontal Size 5. Fail safe (should be the final step).

w

W 5 4 3 2 1

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