Fluke 54200, Руководство пользователя

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How to Use the Instrument
Description and Applications of the Test Patterns
4
4-47
Table 4-4. Crosshatch
Aspect Ratio
4 : 3 16 : 9
Line System Line System
625 525 625 525
Level Y
•
White
•
Black
100%
0%
100 IRE
7.5 IRE
100%
0%
100 IRE
7.5 IRE
Position of crosshatch lines
•
Horizontal lines:
First horizontal line, field1 / field 2.
Distance between horizontal lines
•
Vertical lines:
First vertical line, after start of
line sync pulse
Distance between vertical lines
30/342
21
12.0 µs
2.89 µs
24/287*
18
11.11 µs
2.89 µs
30/342
21
11.85 µs
2.15 µs
24/287*
18
10.96 µs
2.15 µs
* subtract 3 lines for PAL M
Checkerboard
Figure 4-72. Checkerboard, Aspect Ratio 4:3
Figure 4-73. Checkerboard, Aspect Ratio 16:9
Description:
Checkerboard is a full field B/W pattern with
color burst and comprises nine times twelve
(4:3) or nine times sixteen (16:9) squares.
625 525
Level Y Line Systems Line Systems
• White
100% 100 IRE
• Black
0% 7.5 IRE
Applications:
The checkerboard pattern provides a visual
standard for basic picture tube alignments
and gives a clear impression of B/W per-
formance of TV or CTV. Any fault, for
example, in horizontal or vertical synchroni-
zation, deflection or linearity will show up
immediately. Bandwidth can be checked by
observing the vertical transitions. Transitions
from black to white should be sharp.
Furthermore, this pattern indicates mains
hum interference in the synchronization and
no picture interference (Moiré) should occur
(sound eventually to be switched off).