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When replacing the following components marked with a Y  on the 
schematic diagram always check the HV regulation, and if necessary 
re-adjust.

  X :  C517

  Y : 

C517, C521, C522, IC654, L504, T502, T504 (FBT),                        

  

DY, A board, G board

1. Connect an HV static voltmeter to the unused socket of the high-

voltage block. (Fig. 3-1)

2. Power on the set.

3. Display a dot pattern through the VHF/UHF input (PICTURE and 

BRIGHTNESS set to minimum)

4. Check that the HV static voltmeter is reading                                          

31.00 KV  +1.0 KV DC / -2.5 KV DC.

    

 

1. Connect a HV static voltmeter to the unused socket of the high-

voltage block.

2. Power on the set.

3. Display a dot pattern through the VHF/UHF input (PICTURE and 

BRIGHTNESS to minimum).

4. If anode voltage is 31.95kV or higher, change the value of C517 from 

470pF/2kV to 1,000pF/2kV, and confi rm that the high voltage is within 
the range specifi ed above.

5. If anode voltage is 29.45kV or lower, change the value of C517 from 

470pF/2kV to 100pF/2kV, and confi rm that the high voltage is within 
the range specifi ed above. 

 

 

 

    

 

 

  

Remove the cap from
the unused terminal and
connect a static voltmeter
here.

When replacing the following components marked with a Y  on the 
schematic diagram always check the hold-down voltage and re-adjust 
when necessary.

  X :  R536, R545

  Y  :  C516, C536, D506, D507, D522, IC206, IC502, IC654, 

  

L504, R511, R522, R536, R538, R545, R548, R584, T502,              

  

T504 (FBT), DY, A board, G board

1. Unplug connector CN652.

2. Connect an HV static voltmeter to the unused socket of the high-

voltage block.

3. Connect a 220

Ω

/200W resistor, across pin 2 and pin 1 of CN652, 

and connect an external DC power supply (200V, class 2A) to pin 
3 of CN652.

4. First, turn on the external power supply (+B=135V), then turn on the 

power to the set.

5. Display a dot pattern through the VHF/UHF input (PICTURE and 

BRIGHTNESS to minimum).

6. Gradually increase the value of the external DC power supply and 

check that the hold-down circuit operates at a static HV voltmeter 
reading of 33.5±1.0kVdc when the set shuts down.

7. Remove AC power from the set, then remove the 220

Ω

/200W resistor 

and reconnnect CN652.

1. Repeat steps 1-8 above.

2. If hold-down voltage is 34.5kV or higher, remove R536, mount a 

resistor (150k

Ω

, 1/4W : RN) onto R545 instead, and check again if the 

hold-down voltage is within the standard range.

3. If hold-down voltage is 32.5kV or lower, mount a resistor (220k

Ω

, 

1/4W : RN) onto R536 and check again if the hold-down voltage is 
within the standard range.

NOTE: Finish the adjustment as soon as possible.

The following adjustments should always be performed when
replacing IC654.

1. Supply 130V +/- 2V AC to the set.

2. Display a dot pattern through the video-1 input.

3. Set the PICTURE control and the BRIGHTNESS control to minimum.

4. Confi rm the voltage of G BOARD test point TP135V is less than 

137.0Vdc.

5. If step 4 is not satisfi ed, replace IC654 and repeat above steps.

1. Connect the voltmeter between test point TP OVP and ground.

2. Supply 120VAC to the set using an isolation transformer.

3. Set an adjustable external 150-Volt DC power supply to 120 VDc, and 

connect it to test point OVP.  

4. Power on the set.

5. Set PICTURE and BRIGHTNESS controls to minimum.

6. Gradually adjust the external DC supply towards 150 VDc, and 

make sure the set shuts down when the external supply’s voltage is 
between 139 VDC and 159 VDC. 

 

1. Display a color bar signal through the TV’s VHF/UHF input.

2. Mode:  Personal 1 or 2

  PICTURE: maximum 

 

COLOR: minimum

  BRIGHTNESS:  center  

 

COLORTEMP: neutral

3. Enter the service mode.

4. Turn off the blue and red CRTs by changing the data from “1” to “0” 

in category VPNT item 28 RON (red), and item 30 BON (blue).  If this 
step is not followed, the ABL circuit may prevent you from adjusting 
the peak-to-peak amplitude to 1.8 V.

 

5.  Connect an oscilloscope between pin 7 of CN204 (A board) and 

ground.

6. Select adjustment category “VPNT” adjustment item 19 “SCON”, and 

adjust using the 3 or 6 button on the remote so that the wave form 
level is 1.80 ± 0.05Vp-p.

   

    

1.80 ± 0.05 Vp-p 

White

Black

 

7. Press “MUTING” and then “ENTER” to save the adjustment data.

1. Display a color bar signal through a video input.

2. Mode:   Personal 1 or 2

   PICTURE: maximum 

COLOR: center

  BRIGHTNESS: center 

COLORTEMP: neutral

3. Enter the service mode.

4. Connect an oscilloscope between pin 5 of CN204 (A board) and 

ground.

5. Alternately select adjustment category “VPNT” adjustment item #20 

“SHUE” and item #21 “SCOL”, and adjust them so that VB1 = VB4, 
and VB2 = VB3 as shown below.

    

 

VB1

VB2 VB3 VB4

6. Add 2 to the adjusted value of  “SCOL”.

7.Press “MUTING” and then “ENTER” to save the adjustment data.

1. Select VIDEO 4 and display a color bar signal.

2. Mode:     Personal 1 or 2

  PICTURE: maximum 

COLOR: center

  BRIGHTNESS: center 

COLORTEMP: neutral

3. Enter the service mode.

4. Connect an oscilloscope between pin 5 of CN204 (A board) and 

ground.

5. Alternately select adjustment category “DAC”, adjustment item # 0 

“UVSH” and item #1 “UVSC” and adjust them so that VB1 = VB4 and 
VB2 = VB3 as shown below.

    

VB1

VB2 VB3 VB4

6. Press “MUTING” and then “ENTER” to save the adjustment data.

1. Display a color bar signal through the TV’s VHF/UHF input.

2. Mode: Personal 1 or 2

  PICTURE: maximum 

COLOR: minimum

  BRIGHTNESS: center 

COLORTEMP:  neutral

3. Enter the service mode, and then select the PIP (Picture-in-Picture) 

mode.

4. Select an unused video input for the main picture (it must be black), 

and select the tuner for the small picture (it must be showing 
colorbars).

5. Connect an oscilloscope between pin 7 of CN204 (A board) and 

ground.

6. Select adjustment category “PYC”, adjustment item # 0 “PSCN” and 

adjust so that the peak-to-peak voltage is 1.65 ± 0.05Vp-p as shown 
below.

    

1.65 ± 0.05

White

 

 

 

 

7. Press “MUTING” and then “ENTER” to save the adjustment data.

1. Display a color bar signal through the TV’s VHF/UHF input.

2. Mode: Personal 1 or 2.

  PICTURE: 

maximum  

COLOR:  center

  BRIGHTNESS:  center 

 

COLORTEMP: neutral

3. Enter the service mode and select the PIP mode.

4. Connect an oscilloscope between pin 5 of CN204 (A board) and 

ground.

5. Select an unused video input for the main picture (it must be black), 

and select the tuner for the small picture (it must be showing 
colorbars).

6. Alternately select adjustment category “PYC”, adjustment item # 2 

“PHUE” and item #3 “PCOL” and adjust them so that VB1 = VB4 and 
VB2 = VB3 as shown below.

 

    

VB1

VB2 VB3 VB4

 

   

   

   

 

7. Press “MUTING” and then “ENTER” to save the adjustment data.

1. Select the video-1 input with no signal applied (the screen should 

be black).

2. Enter the service mode.

3. Press the “Volume +” button so that the volume bar graph is displayed.

4. Check to make sure the bar graph is centered on the screen 

horizontally.  If necessary, select  adjustment category “OP”, 
adjustment item # 0 “DISP”, and adjust so that the bar graph is 
centered.  Adjust the data 1 step at a time, and then display the bar 
graph again to check its position.

 

    

 

X1 = X2

X1

X2

 

5. Write the data into memory, press “MUTING” and then “ENTER”.

1. Select the PIP mode.

2. Display any signal in the PIP window.

3. Alternately select adjustment category “PIP”, adjustment item # 18 

“POFV” and item #19 “POFH” and adjust so that the PIP window is 
equally spaced from the screen edge in each position on the screen 
as shown below.  Use the POSITION button on the remote to change 
the screen position of the PIP window.

    

 

X1-X2 < 0.25 sq

    

 

Y1-Y2 < 0.25 sq

 

    

Y2

X2

X1

Y1

 

4. Write the data into memory,  press “MUTING” and then “ENTER”.