Grass Valley AMX-3981 2014 - Manual (Page 23)

GUIDE TO INSTALLATION AND OPERATION
AMX-3981 | 17
0 line and -31.76
µs to 0 line and 31.76 µs
0 line and 31.76
µs to 1 line and 31.76 µs
etc.
Practical examples:
Example 1: we have two SD (525) sources, one that indicates an offset of -25
µs with respect to the reference (A)
and the other an offset of -35
µs (B). We know that a clean switch region limit is present at -½ line, which corresponds
to -31.76
µs. We can now determine that this switch will not be clean, because the two sources are on opposite sides
of the limit, and are therefore not in the same clean switch region.
Ref signal
Signal A
Signal B
H=½ line H = 0
Line = 0
H = 0
Line = -1
H=0
V=1
H=0
V=1
-25us
-31.76us
-35us
clean switch region #1 clean switch region #2
Example 2: We have two SD (525) sources, one that indicates an offset of 50
µs with respect to the reference (A) and
the other an offset of 40
µs (B). We know that a clean switch region limit is present at + ½ line and another one at ½
line plus one line. These correspond to 31.76
µs and 95.28µs. We can now determine that this switch will be clean,
because the two sources are inside the same clean switch region.
Ref signal
Signal A
Signal B
H=½ line H = 0
Line = 0
40us
31.76us
50us
clean switch region #2
H=½ line
H=0
V=1
H=0
V=1
H = 0
Line = 1
H=½ line
clean switch region #3
95.28us