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I. PLEASE READ BEFORE ATTEMPTING SERVICE
1. Never disconnect any leads while receiver is in operation.
2. Disconnect all power before attempting any repairs.
3. Do not short any portion of the circuit while power is on.
4. For safety reasons, all parts replaced should be identical, ( for parts and part numbers see parts list ).
5. Before alignment the set must be pre-heated for 30 minutes or more and erase magnetism thoroughly
from CRT front chassis frame by erase coil.
II. B+ ADJUSTMENT
1. Connect a digital voltmeter to C406 + and Ground.
2. Set Brightness Contrast to minimum.
3. Adjust SCREEN Volume on FBT until the picture can just been seen.
4. Adjust VR901 to obtain a reading of 143 + 0.5V .
III. FACTORY ADJUSTMENT SERVICE REMOTE CONTROL
Press SERVICE REMOTE button to direct select item.
1. Use( ) or ( ) button select item.
2. Use ( ) ( )button to adjust item value.
*REMARK: Normal REMOTE CONTROL does not have this function.
IV. AGC ALIGNMENT
1. Receive CH69 (UHF) and input field strength.60 dBuV+2dB.
2. Connect a digital Voltmeter between the TUNER AGC Terminal and Ground.
3. Select R AGC item, Adjust the value to 3F, and then adjust the AGC voltage drop down 0.4V.
Remark: (1) The drop down voltage should be more than and tends to 0.4V.
(2) No Observable noise can be seen.
V. VERTICAL HEIGHT ADJUSTMENT
NTSC (60Hz)
1 . Receive Mono scope Pattern (60Hz).
2 . Select HIT item adjust value to normal regular picture.
VI. VERTICAL LINEARTY ADJUSTMENT
NTSC (60Hz) Adjustment
1 . Receive Cross hatch Pattern (60Hz)
2 . Select VLIN item adjust value to normal regular picture.
ALIGNMENT INSTRUCTION
SM-74PM P.7
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