Vertical Adjustments; Horizontal Adjustments - Beehive International B102 Service Manual

In all cases, the output DC impedance of the video signal source must be 500 ohms,
or less.
3.4 VERTICAL ADJUSTMENTS
There is a slight interaction among the vertical frequency, height, and linearity
controls. A change in the height of the picture may affect linearity.
(!) Apply video and synchronization signals to the monitor.
(2) Set the vertical frequency control, R116, near the mechanical
center for its rotation.
(3) Adjust the vertical height control, R124, for desired height.
(4) Adjust the vertical linearity control, R121, for best
vertical linearity.
(5) Remove the vertical drive signal from the unit. Or,
alternatively, use a short jumper lead, and short the vertical
drive input terminal of the printed circuit card edge
connector to ground.
(6) Readjust the vertical frequency control, R116, until
the picture rolls up slowly.
(7) Restore vertical drive to the monitor.
(8) Recheck height and linearity.
3.5 HORIZONTAL ADJUSTMENTS
Raster width is affected by a combination of the low voltage supply, width
coil LlOl, and the horizontal linearity sleeve located on the neck of the CRT
beneath the yoke.
(1) Apply video and synchronization signals to the monitor. .
insert the horizontal linearity sleeve about 2/3 of its
length under the yoke. (If you received a monitor from
the factory in which the placement of the linearity sleeve
has been determined, make a mark on the sleeve and
reinsert the sleeve to this mark when removal of the yoke
and linearity sleeve are required.) If the linearity sleeve
is inserted farther than necessary, excessiye power will
be consumed, and the horizontal output circuitry could
be overstressed.
(2) Adjust the horizontal width coil, LlOl, for the desired width
(3) Insert the linearity sleeve farther under the yoke to obtain
the best linearity. Although this adjustment will affect
A-7