Grass Valley K-Frame Installation Planning Guide - Manual (Page 48)

48 K-FRAME — Installation Planning Guide
Section 3 — K-Frame Cabling
Time Zones and the Autotiming Window
Each ME has a fixed amount of delay from its input to output. To allow
reentries to remain in time, ME timings are staggered such that the up
stream ME outputs are in time (or earlier) than down stream ME inputs. A
5 ME production switcher has six time zones to accommodate reentry
through all the MEs to any output. When all MEs are cascaded into each
other, the most up stream ME is in the earliest time zone. Aux buses and
other outputs are always in the latest time zone. The overlapping range of
all the autotimers is the published autotiming window for the switcher.
Figure 4. Production Switcher Time Zones
Any source fed to the switcher must be within the autotiming range of all
six time zones. If not, the source will be in time on some MEs but not on
others. As illustrated in the figure, a source centered in one time zone’s
autotiming range can be too early or late for other switcher time zones.
If a signal falls just outside the autotiming window, that image will be
shifted one line up or down. On SD systems a shift of one line could be
Autotiming Range
M/E
Processing
Delay
Time
Zone
1
Autotiming Range
M/E
Processing
Delay
Time
Zone
2
Autotiming Range
M/E
Processing
Delay
Time
Zone
3
Autotiming Range
M/E
Processing
Delay
Time
Zone
4
Autotiming Range
M/E
Processing
Delay
Time
Zone
5
Autotiming Range
Aux
Output
Delay
Time
Zone
6
Autotiming
Window
Center of
Autotiming Window
Center of Time Zone 5
Autotiming Range
Too Late for Time Zone 1
Center of Time Zone 1
Autotiming Range
Too Early for Time Zones 5 and 6
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