JVC AV-21D116, Service Manual

Page: 11 / 63

(No.YA396)1-11
SECTION 4
ADJUSTMENT
4.1 ADJUSTMENT PREPARATION
(1) There are 2 ways of adjusting this TV : One is with the
REMOTE CONTROL UNIT and the other is the
conventional method using adjustment parts and
components.
(2) The adjustment using the REMOTE CONTROL UNIT is
made on the basis of the initial setting values. The
setting values which adjust the screen to the optimum
condition can be different from the initial setting
values.
(3) Make sure that connection is correctly made AC to AC
power source.
(4) Turn on the power of the TV and measuring instruments for
warming up for at least 30 minutes before starting
adjustments.
(5) If the receive or input signal is not specified, use the most
appropriate signal for adjustment.
(6) Never touch the parts (such as variable resistors,
transformers and condensers) not shown in the adjustment
items of this service adjustment.
4.2 PRESET SETTING BEFORE ADJUSTMENT
Unless otherwise specified in the adjustment items, preset the
following functions with the REMOTE CONTROL UNIT.
4.3 MEASURING INSTRUMENT AND FIXTURES
(1) DC voltmeter (or digital voltmeter)
(2) Oscilloscope
(3) Signal generator
(Pattern generator : PAL / SECAM / NTSC)
(4) Remote control unit
4.4 ADJUSTMENT ITEMS
„
CHECK ITEM
• B1 VOLTAGE check
„
TUNER / IF CIRCUIT
• IF VCO adjustment
• DELAY POINT adjustment
„
FOCUS
• FOCUS adjustment
„
DEFLECTION CIRCUIT
• V.HEIGHT / V.POSITION adjustment
• H. POSITION adjustment
• V.LINEARITY / V.S-CURVE adjustment
„
VIDEO CIRCUIT
• WHITE BALANCE adjustment
• SUB BRIGHT adjustment
• SUB CONTRAST adjustment
• SUB COLOUR adjustment
• SUB TINT adjustment
• SECAM BALACK OFFSET adjustment
„
VSM PRESET SETTING
• VSM PRESET setting
Item Preset value
PICTURE MODE BRIGHT
TINT / COLOUR / BRIGHT / CONT. / SHARP Centre
VNR OFF
BLUE BACK OFF
OFF TIMER OFF
AUTO SHUT OFF OFF