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Time zones and the autotiming window – Grass Valley K-Frame Installation Planning Guide Jul 07 2014 User Manual

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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 (

Figure 4

). 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.

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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