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ADJUSTMENT
A. Safety precautions
1. It is safe to adjust after using insulating transformer between the power supply line and
chassis input to prevent the risk of electric shock and protect the instrument.
2. Never disconnect leads while the TV receiver is on.
3. Don't short any portion of circuits while power is on.
4.
The Adjustment must be done by the correct appliance. But this is changeable in view of
productivity.
B. Adjustment procedure
(adjustment content and adjusting point diagram)
HT-2599 Adjustment Instructions
1. Equipment, instruments and tools:
(1) One 25
″
factory-assembled color TV set
(2) One 100MHz oscilloscope
(3) One three-digit voltmeter
(4) One AC voltage-stabilized source
(5) Factory standard signal cable input system
(6) One user’s remote controller
(7) One adjusting rod
2. Adjusting method of main voltage (111V) or (134V), line amplitude, pincushion
correction and intermediate frequency detection (38.9 MHz):
(1) Connect the main baseboard to a 25
″
factory-assembled color TV set and connect the
company’s adjusting signal.
(2) Switch on 150~250V AC main power supply and receive the electronic circular signal.
Adjust accelerating pole and focusing pole to appropriate position. Press the picture
memory mode button (PP) on the user’s remote controller to get into “MEMORY2”
status.
(3) Ground the black rod of digit voltmeter and connect the red rod to R544. Adjust the
potentiometer RP551 (2K) until the digit voltmeter indicates 111
±
0.5 or 134
±
0.5.
(4) Receive electronic circular signal, use user’s remote controller to enter “MEMORY 2”
status. Adjust the potentiometer RP432 to achieve the best status of line size
(90%~92%).
(5) Receive grid signal and press user’s remote controller to enter the “MEMORY 1”
status. Adjust the potentiometer RP431 to minimize the pincushion distortion or
Summary of Contents for 21F99
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