Toshiba 28N03F Service Manual page 10

ELECTRICAL ADJUSTMENTS
ITEM ADJUSTMENT PROCEDURE
FOCUS VR ADu. 1. Display black cross bar pattern from EXT source.
2. Adjust the FOCUS control (on T7461) for well defined scanning lines on the picture
screen.
1. Set CONTRAST to minimum, and
BRIGHTNESS to center by adjusting
user controls.
2. Use external signal source to get white
cross-bar of inside pattern.
3. Select BRTC (brightness correction),
and adjust the .<] — /+ button to reduce
the value so that white portion of inside
pattern slightly light.
4. Adjust J —/+ button to increase the
data value of BRTC, and set it just
before the difference between the belt of
vertical retrace and the border of black Beit of vertical retrace
portion of inside pattern is visible.
After that, return vertical height and
contrast.
SUB-BRIGHTNESS
(BRTC)
Note: Constrict the picture height
until the vertical retrace line
appears adjusting the item
HIT (HEIGHT).
HORIZONTAL POSITION
ADJUSTMENT (HPOS)
. Use external signal source to get
black or white cross-bar signal and
select service mode.
2. Select either HPOS (Horizontal
picture phase) or VPOS (Vertical
picture phase) with CHANNEL A, ¥
buttons, and adjust horizontal or
vertical picture position in the center
of screen with VOLUME 41 - /+
buttons.
VERTICAL POSITION
ADJUSTMENT (VPOS)
. Use external signal source to get
black or white cross-bar signal and
select service mode.
2. Select HIT (Vertical amplitude) with The first
CHANNEL A, ¥ buttons, and adjust
vertical amplitude with VOLUME
«<1 — /+ buttons so that vertical am-
plitude lacks a little.
3. Adjust vertical amplitude with VOL-
UME .1—/+ buttons so that the first
bar on cross-hatch signal touches
edge of screen.
VERTICAL AMPLITUDE
ADJUSTMENT (HIT)
—~10-—
l a a St te e R C e a