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8.2.2
FAILSAFE
FIGURE 8-21
For TriCaster rack mount units, multi-tiered ‘Always on Air’ hardware and software failsafe systems provide
confidence that – short of a complete power failure – the show will go on. Video pass-through ensures that
as long there is AC power, audio and video from Input 8 (on 4RU models) or Input 4 (2RU models) are routed
to Output 1 in a case of catastrophic software condition. If at all possible, streaming output and recording
also continue even if all else fails.
In some studio settings, however, more elaborate hardware failsafe systems may be in use. Typically, such
systems take over broadcast duties whenever the output signal fails. In this sort of pipeline, TriCaster’s
failsafe video passthrough mechanism (which ensures that video output continues even in catastrophic
circumstances) can actually prevent the external system from engaging. For this reason, a Failsafe control
group has been added to the Output tab for TriCaster rack-mount models. It provides a switch to let you
disable the A/V passthrough when necessary. By default, A/V passthrough is off.
Hint: Only use fail-safe when a stable video source is connected to video Input 8.
8.2.3
GENLOCK TAB
TriCaster’s Genlock feature allows it to ‘lock’ its video output to a
reference video signal supplied to its Genlock input connector. (Note
that TriCaster 410, TriCaster Mini SDI and Mini do not provide
Genlock support.)
This synchronizes TriCaster output to other external equipment
locked to the same reference. Genlocking is not a requirement, but it
is very beneficial, and you should definitely use it if you have the
capability.
TriCaster mixes and switches output from up to eight directly
connected local camera sources (4RU models). Miniscule local timing
differences between these may force tiny delays during switching
operations, which can also contribute to throughput latency. Thus,
serving i) TriCaster’s Genlock input and ii) other video devices in the
chain with a single reference is the best approach.
You could think of it this way:

Genlocking your cameras has the effect of locking their output together,
ensuring optimal synchronization for live switching. This may result in
throughput latency benefits.
Hint: The term “genlock” refers to
“generator locking”.
Professional video devices often
provide a “genlock input”, which
allows an external reference signal
(often referred to as ‘house sync’)
to control its video timing.
The output of video devices
connected in this manner is
synchronized to the reference
signal, and they are referred to as
‘genlocked’.