Sharp 8C221, Руководство по обслуживанию

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High voltage is not adjustable but must be checked to
verify that the receiver is operating within safe and efficient
design limitations
as
specified:
If
Remove cabinet back.
Operate receiver for at least minutes, with strong air
signal or test signal properly tuned in.
Set Brightness and contrast controls to maximum
position.
Connect an accurate high voltage meter to CRT anode.
Reading should be (at 1
correct reading cannot be obtained, check circuitry for
malfunctioning components.
FOCUS
Adjust the Focus located on the rear of the
TV chassis, for maximum and fine picture
detail with Brightness and Contrast controls set at normal
viewing levels.
VERTICAL SIZE AND LINEARITY
The Vertical Linearity control primarily affects the
top of the raster while the Vertical Size control
primarily affects the bottom of the raster. However,
there is some interaction between these two controls.
Vertical Centering properly positioned and Brightness and
Contrast controls adjusted for normal picture, alternately
adjust Vertical Linearity and Vertical Size controls to
obtain a linear picture.
HORIZONTAL OSCILLATOR ADJUSTMENT
The receiver should be operating for at least minutes
before proceeding.
Tune in a local station and set the Horizontal Hold
control at the center of its rotation.
Connect a short clip lead between test point
and ground.
Adjust the Horizontal Frequency Control to
obtain minimum horizontal movement of the picture.
Remove a short clip lead between test point and
ground.
Check the operation of the Horizontal Hold control to
verify that the picture is synchronized with the
control set at the mechanical of its range.
RF ADJUSTMENT
The receiver should be operating for at least minutes
before proceeding.
Connect a input signal to the antenna terminal.
Connect to
Fully turn RF control counter-clock-
wise.
Observing the indication of slowly turn RF
control clockwise and fix it when the
voltage starts to fall.
ADJUSTMENT
The control is adjusted at the factory.
However, should readjustment be required, proceed
as
follows:
Operate receiver for at least minutes.
Connect positive lead of to negative lead
to is ground.
Rotate Adjust control to clockwise
and/
or counter clockwise until a reading of DC
Remove to
CAUTION: Do not exceed volt for protecting
the set from failure.
H-SIZE ADJUSTMENT
Since the horizontal amplitude of receiver has been com-
pletely adjusted before delivery from the factory, normally
readjustment should not be required.
However, if it
becomes necessary for any reasons, take the following steps.
Receive cross-hatch pattern.
Rotate H-Size coil
until over scanning is more
than 6 percent.
CENTERING ADJUSTMENT
H-Center Adjustment:
If the picture is one-sided from right to left of the screen,
rotate H-CENT adjust control
until the picture is
centered.
Adjustment:
If the picture is one-sided from top bottom of the
screen, change V-CENT adjust tip to adjust so that the
picture is centered.
PINCUSHION ADJUSTMENT
The pin-cushion adjustments are at the factory and
normally need no further adjustment. However, if necessary,
corrections can be made by adjusting for straight horizontal
lines at the top and bottom of the rester.
The receiver should be allowed to operate for at least five
minutes with a cross-hatch pattern displayed on the screen.
Top and Bottom Pincushion Adjustment
Adjust the Pincushion coil to move the maximum
curvature of the horizontal lines to the center of the
screen.
Adjust the Pincushion Transformer Magnet so as
to straighten out the horizontal lines at both the top and
bottom of the screen.
Side Pincushion Adjustment
Rotate the Side Pin. Phase control until the pin-
cushion distortion is at the of screen.
Rotate the Side Pin. Amp. control to compensate
for pincushion distortion until vertical lines at both sides
of screen are straight .
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