6-64
DNW-A22/A22P
15. Guard Band Width Adjustment
Measuring equipment: Video monitor
(1) Enter A35 : DM VR 4 of the maintenance mode
(2) Confirm the setting data of following items of A35 : DM VR 4.
n
Some setting data are different according to the board number suffix (XX of 1-648-541-XX) of DM-
89 board.
Item of A35 : DM VR 4
Setting data for DNW-A22
Setting data for DNW-A22P
Suffix-13
Suffix-14 and higher
Suffix-13
Suffix-14 and higher
GUARD BAND METAL-Y
38
1D
29
27
GUARD BAND METAL-C
21
1C
16
23
GUARD BAND OXIDE-Y
48
32
3B
2F
GUARD BAND OXIDE-C
30
31
16
29
(3) Playback the color-bar signal portion (14:00 to 17:00) of the alignment tape CR5-1B or CR5-1B PS
in the JOG mode. (DNW-A22: CR5-1B, DNW-A22P: CR5-1B PS)
(4) Turn the search dial until guard band appears at the center on the video monitor screen.
(Refer to Figure 1 on next page.)
(5) METAL, Guard band width confirmation
Confirm the following specifications. If both are satisfied, go to step (8).
If not, perform step (6) or (7).
Specification 1:
Guard band width is below a third of video display screen’s height.
Specification 2:
Guard band width of C side > Guard band width of Y side
(6) If the specification 1 is not satisfied:
Subtract 1 from each data value of GUARD BAND METAL-Y and GUARD BAND METAL-C,
then perform the confirmation of step (5) again.
(7) If the specification 2 is not satisfied:
Add 1 to the data value of GUARD BAND METAL-C, then perform the confirmation of step (5)
again.
(8) METAL C confirmation
Playback the color-bar signal portion (14:00 to 17:00) of the alignment tape CR5-1B or CR5-1B PS
in the VARIABLE
+
1 time speed mode (or the search
+
1 time speed), and confirm the following
specification. If satisfied, go to step (10). If not, perform step (9).
(DNW-A22: CR5-1B, DNW-A22P: CR5-1B PS)
Specification 3:
The picture (color-bar) on the video monitor is colored.
(The C signal is not fully muted.)
(9) If the specification 3 is not satisfied:
Subtract 1 from the data value of GUARD BAND METAL-C, then perform the confirmation of step
(8) again.
(10) Eject the alignment tape CR5-1B/CR5-1B PS.
6-3. DM-89 Board Replacement