Table of Contents
Advertisement
7.ELECTRICAL 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 appliances. But this is changeable in view of
productivity.
5. Unless otherwise noted, set the line voltage to 220Vac±20%, 50/60Hz.
B. Adjusting items
1. Equipment, instruments and tools:
(1)
One process assembling machine for 21" color TV
(2)
One 100MHz oscilloscope
(3)
One three-digit voltmeter
(4)
One AC regulated power supply
(5)
Factory standard signal cable input system
(6)
One user remote controller
(7)
One adjusting tool
2.
Adjusting method of main voltage (115V) and intermediate frequency detection
(38.9 MHz):
(1) Connect the main baseboard to a 21" factory-assembled color TV set and connect the
company's adjusting signal.
(2) Switch on 220V 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 R553. Adjust the
potentiometer RP501 (2K) until the digit voltmeter indicates 115 0.5 V.
(4) Use factory special remote controller for adjustment (V.) by pointing it to the baseboard
infrared receiver and pressing S-PVOC button. Then the factory-assembled color TV displays
AFT (dark field)---AFT OK (with signal or noise), intermediate frequency detection
(38.9MHz) adjustment finishes.
37
Advertisement
Table of Contents
