Philips PTV800, Руководство по обслуживанию

Страница: 86 / 567

CRT SCREEN CENTERING (Mechanical)
1.
Locate the Screen Center by placing strings diagonally across the viewing area of the
screen from corner to corner. The Screen Template, if centered correctly on the screen, can
also provide the center point location.
2. Enter the "Service Setup Mode" (06-25-96-Menu-Menu) and confirm approximate register
values of the following registers: Note: Confirming the following register values is not
required if the Small Signal or Large Signal Boards have not been replaced or altered.
Function Register Value
Picture Height 37 48
V Linearity 38 0F
V S Correction 39 0E
Vertical Shift 40 00
V Comp 41 00
Picture Width 42 20
East/West Parabola 43 10
East/West Corner 44 0E
Trapezium 45 39
Horz Comp 46 00
V SS Corr 47 00
Horiz Phase 48 11
3. Connect a Signal Source (pattern generator) to the antenna terminal of the set. A signal
source must be present while following these procedures.
4. Enter the Convergence Service Mode as described above in the Convergence Service Mode
Procedure.
5. Place a jumper wire from pins 1 to 2 of test point 4 (tp4) on the convergence panel.
6. Select "1" Green Geometry from the Convergence Service Mode Menu. Cover the Red and
Blue output lens using a 7" X 7" piece of cardboard.
7. The highlighted icon (cross) maybe visible on the left side of the screen about half way up.
Position the icon at the screens approximate center by pressing the M on the remote
transmitter 3 times.
8. Using the Centering tabs of the yoke, position the highlighted Green icon to the screen center
as defined by the diagonal strings positioned across the viewing area of the screen or using
the center point on the screen template.
Note: In some cases there may be insufficient
range with the centering tabs to position the Green icon to the screens center. In this case
position the icon as close as possible to the screen center.
9. Confirm the centering by viewing the screen from the front of the unit.
10. Return to the Convergence Service Mode Menu by selecting number 3 on the remote
transmitter. Select number "2" on the remote to activate the "Red to Green" Convergence.
Cover the Green and Blue output lenses with a 7" X 7" piece of cardboard. Repeat step 7
through 9 using the Red yoke Centering Tabs.
11. Return to the Convergence Service Mode Menu by selecting "3" on the remote transmitter.
Select "2" to repeat convergence. Select "3" on the remote to activate the "Blue to Green
Convergence". Cover the Red and Green output lenses with a 7" X 7" piece of cardboard.
Repeat step 7 through 9 using the Blue yoke Centering Tabs.
12. Exit the convergence mode by selecting the Status Exit function on the remote transmitter.
Remove the 7" X 7" pieces of cardboard from the output Lenses. CRT centering is complete.
13. Remove the jumper from TP4 on the Digital Convergence Module.