TOSHIBA 40H80
Manual de Servicio

ELECTRICAL ADJUSTMENT
ITEM �H (free-running frequency of Hor. oscillator) ADJUSTMENT PROCEDURE 1. Receive NTSC signal. 2. Short the terminal �TP +9V � and the terminal � TP (Free run) � on the signal board with a jumper wire. 3. Connect the probe of frequency counter to the lead of R426 and GND. 4. Adjust the frequency to �31.47±0.2 kHz� by turning R4055. 5. Disconnect the shorted wire, then confirm that the picture is synchronized. 1. 2. 3. 4. Receive NTSC signal. Call up the adjustment mode display, then select the item VCEN. Press the VOLUME s or t button to get the voltage 0±10 mV. Measuring terminals are TP-V and TP-G on SIGNAL Board.

VERTICAL POSITION (VCEN)

SUB-BRIGHTNESS (BRTC)

SPECIFIC INFORMATIONS GENERAL ADJUSTMENTS

1. Constrict the picture height until the vertical retrace line appears adjusting the HEIGHT control on the MAIN board. 2. Adjust the CONTRAST to the minimum and BRIGHTNESS to the center. 3. Enter the service mode, then select �BRTC� register. 4. Adjust the data value so the belt of vertical retrace line just disappear. 5. Adjust the CONTRAST for the desired contrast. 6. Adjust the HEIGHT control.
Vertical retrace line

SUB-COLOR (SCOL) SUB-TINT (TNTC)

Receive color-bar signal from color-bar generator. Adjust the BRIGHTNESS and CONTRAST to the center (RESET status). Connect oscilloscope to TP501on the MAIN board. Blue Enter the service mode, then select �SCOL�. Magenta Temporarily adjust the data value to achieve about 1V0-p of blue bar. 6. Select �TNTC� register. 0 7. Adjust the data value to obtain the blue bar to magenta bar ratio of 3:2 as shown. 8. Select �SCOL� register. 9. Adjust the data value to achieve 1.8V0-p of blue bar on scope. 10. Check the picture with off-air signal.

1. 2. 3. 4. 5.

3 (1.8V0-P)

2

PICTURE POSITION 1. Receive NTSC signal. (HPOS) 2. Call up the adjustment mode display. 3. Select the item �HPOS�, and adjust the data to �66H�. 4. Adjust the picture position alternately by turning CENTERING MAGNETS for proper picture position. 5. Check the picture with off-air signal. WIDTH (WID) 1. Receive NTSC signal. 2. Select the "FULL" mode by PIC SIZE button on Remote Control. 3. Call up the adjustment mode display, then select the item WID. 4. Press the VOLUME s or t button to get the picture so that left and right eddes of video signal begin to lack. 5. Press the VOLUME s button to advance the data by 12 steps. NOTE: Check the horizontal picture position is correct.

� 12 �