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SERVICE ADJUSTMENTS
PV154 - 923-03506
3-19
ZP26/28 - SERVICING
Left of Center and Blue is offset Right of center. Please
use the following information to accurately offset Red
and Blue from center. Also see Overlay Dimensions for
further details.
PREPARATION FOR ADJUSTMENT:
· Video Control should be set at Factory Preset
condition.
· Static Focus adjustment should be finished.
ADJUSTMENT PROCEDURE
1. With Power Off, press the Service Only switch on
the Convergence PWB. While holding the Service
Only Switch down, press the Power On button. Pic-
ture will appear without convergence correction.
2. Press the Service Only Switch to receive the DCU
cross-hatch signal.
3. Turn the centering magnets of Red, Green and Blue
and adjust so that the center point of the cross-
hatch pattern satisfies the diagram below. (DCU
data is cleared). Remember Green is Centered. Red
is to the left of Green and Blue is to the right of
Green as indicated below.
o All Vertical positions are geometric center of screen.
o Parameters are +/- 2mm.
MODEL
RED OFFSET LEFT
OF CENTER
BLUE OFFSET
RIGHT OF CENTER
ASPECT
65"
15mm
25mm
16 X 9
61"
15mm
25mm
16 X 9
56"
15mm
25mm
16 X 9
VERTICAL SIZE ADJUSTMENT
VERTICAL SIZE:
· Receive an NTSC signal.
· Video Control should be set to Factory Preset
condition.
· Convergence should not be corrected.
ADJUSTMENT PROCEDURE:
1. With Power Off, press and hold the Service Only
Switch on the Convergence PWB, then press the
Power Button and Release. (Digital Convergence
data is cleared). Then release the Service Only
Switch. DCU Grid appears.
2. Adjust using R607 (Vertical Size Adj. VR) to match
marks on the Overlay. (See Figure Below)
3. Turn Power Off.
NOTE: Centering magnet may be moved to facilitate.
Distance is important, not centering.
ALTERNATE METHOD:
Adjust Vertical Size until the size matches the chart
below.
ALTERNATE METHOD:
Adj Vert Size until the size matches the chart below.
Scrn Size
56”
61”
65”
Scrn Format
NORM
NORM
NORM
L=
590
645
690
All Adjustments are +/-5mm
HORIZONTAL SIZE ADJUSTMENT
PREPARATION FOR ADJUSTMENT
· Display Mode NORMAL
· Install the correct Overlay.
· Input an NTSC Signal.
· Digital Convergence RAM should be cleared.
· With Power Off, press the Service Only switch on
the Convergence PWB. While holding the Service
Only Switch down, press the Power On button and
Release. DCU Grid will appear without convergence
correction.
NOTE: After entering DCAM, with each press of the Service
Only Switch, the picture will toggle between Video
mode and DCU Grid.
· Project only the Green raster by selecting Green
Adjustment mode and pressing the MENU button.
ADJUSTMENT
1. Adjust using R711 (Horz. Size Adj. VR) to match
marks on the Overlay. (See Figure Below)
2. Press “Power Off” to exit DCAM. (Digital Conver-
gence Adjustment Mode.)
ALTERNATE METHOD:
Adj Horiz Size until the size matches the chart below.
Screen Size
56”
61”
65”
Screen Format NORM
NORM
NORM
L=
1165
1270
1355
All Adjustments are +/-5mm
BEAM FORM ADJUSTMENT
PREPARATION FOR ADJUSTMENT
IMPORTANT: Screen format should be “NORMAL”.
1. Pre Heat, Cut-Off, Pre-optical focus, DCU Phase
Data, H. Pos Course, Raster Tilt, Beam Alignment,
Raster Position, Vertical and Horizontal Size ad-
justment should be completed.
2. Brightness: 90%, Contrast: Max.
3. Input a NTSC DOT signal.
ADJUSTMENTS PROCEDURE:
4. Green CRT beam shape adjustment.
5. Short-circuit 2P sub-mini connectors on Red and
Blue CRT PWB to project only the Green beam.
6. Turn the green static focus VR fully clockwise.
7. Make the dot at the screen center a true circle,
using the 4-Pole magnet shown in (Figure 1 be-