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ELECTRICAL ADJUSTMENTS BEKO Chassis 12.6
ACCESSING THE SERVICE MODE

To enter the Service Mode, `Service In/Out" button on the Service Remote Control or activate the
"Picture Menu" with the user remote control and press "8500".
"Red" , "Green", "Yellow" and "Blue" Teletext buttons are for Feature Setup, Geometry, White Balance
and AFC menus respectively.
Press "0" button to exit the Service Mode.

1. POWER SUPPLY VOLTAGE

Connect a digital voltmeter to the cathode of D607 diode at the AV1 mode of the TV and set the
screen voltage to the minimum. Adjust the main supply voltage +B with P601 potentiometer to the
following voltage value. Adjust the screen potentiometer to the level where a picture is just visible.

14" A34LPE02X01 106 VDC
20" A48ECR143X51 118 VDC
21" A51EER133X41 118 VDC

2. AFC ADJUSTMENT

Before starting the adjustment follow the procedure below:
Enter service mode, change "VIDEO" header to the "NEW". Then exit from service mode.
Remarks:
1. The procedure above must always be done after replacing the Video IC (IC101) or EEPROM IC.
2. AFC adjustment must be done again when "VIDEO" header became "NEW" accidentally.

For BG, DK, I, L standards (38.9 MHz) : Supply a 471.25 MHz BG system colour bar RF signal to the set by
a pattern generator and find this signal in "setup" menu (C21). In order to deactivate AFT loop, shift
value of "fine tuning" from central point by one unit and then shiftback to the central point again (2
small vertical lines are seen in the scale on central point). Store the channel by selecting "Store" and
pressing "OK" button. Enter Service Mode and press "Blue" Teletext button. Adjust the "AFT38" item of
service menu to read a value between "78" and "7C" (hexadecimal) on the right part of the screen.
For example:
AFT38 89 7B

For SECAM L' Standard (33.9 MHz): Supply a 55.75 MHz, L' system colour bar RF signal to the set by a
pattern generator and find this signal in "setup" menu (C02). In order to deactivate AFT loop, shift
value of "fine tuning" from central point by one unit and then shiftback to the central point again (2
small vertical lines are seen in the scale on central point). Store the channel by selecting "Store" and
pressing "OK" button. Enter Service Mode and press "Blue" Teletext button. Adjust the "AFT33" item of
the service menu to read a value between "78" and "7C" (hexadecimal) on the right part of value of
item "AFT38". For example:
AFT38 : 76 78
AFT33 : 65

3. AGC ADJUSTMENT

Apply a signal at the channel 32 with 70