Studio Technologies 5150 V.1 - Manual (Page 21)

Model 5150 User Guide Issue 5, March 2014
Studio Technologies, Inc. Page 21
Model 5150
Video Generator Module
input mode. Whenever a valid SDI signal is
connected to the selected Model 5150 input
it will immediately be routed to the coaxial
(BNC) and, if present, optical SDI outputs.
The situation is a little different when a valid
signal that’s been connected to the selected
SDI input is subsequently removed. When
the Model 5150 detects that an SDI input
signal is no longer present the SDI output
may switch to an image with a solid-gray
color. Depending on the module’s configu-
ration this color may remain active for up
to seven seconds. This solid-gray image
provides a benign warning to users that the
normal SDI source is no longer present.
During this time period it’s expected that
any on-air use of the Model 5150’s output
can be terminated without alerting viewers
that anything is amiss. This solid-gray im-
age can also be helpful as a marker when
editing recorded video. After the configured
interval has elapsed the internal generator
will output either the “720” or “1080” stored
image.
It’s also possible that the Model 5150 has
been configured to not output the solid-gray
video signal. In this case, when the module
detects that an SDI signal is no longer
present on the SDI input, the SDI output
will directly switch to the stored image.
It’s important to note that the Model 5150
does not perform a smooth transition when
switching between an external SDI source
and the internally-generated video signals.
The same holds true when the internal
color or image generator is active and then
a valid source is connected to the selected
SDI input. The SDI output does not stay
“locked” during the transition as the circuitry
in the Model 5150 was not designed to
that level of sophistication. This shouldn’t
cause an operational issue as the Model
5150 was not designed to be “on air”
during those transitions; the changeover
process is not seamless by design. One
can assume that up to two seconds of
interruption will occur during transitions but
typically it will be considerably shorter.
Full-Time Video Generation
A configuration selection allows the Model
5150 to act as a full-time video generator.
In this case the selected SDI input will only
be used as an external timing reference.
The front-panel SDI Input LED will light
whenever a valid signal is connected to
the selected SDI input. But the SDI input
source will only serve as a timing refer-
ence. Its video and related data (e.g., em-
bedded audio) will not pass through to the
SDI output(s). The stored video image will
always be present on the SDI output(s).
Output Format and Rate
When a valid signal is connected to the
selected SDI input it will be routed to the
SDI output at the identical format and rate
of the source. When the SDI input is no
longer present the internally-generated
signal will become active and be routed to
the SDI output. The format and rate of the
internally-generated SDI signal will depend
on parameters that are stored within the
Model 5150. Whether these parameters
can change depends on the configuration
of the module’s SDI output image format/
rate mode. Typically, the mode will be set
for Auto Select which allows the Model
5150 to revise its parameters by following
the format and rate of the connected SDI
signal. This ensures that the Model 5150
can generate an SDI signal that matches
the requirements of a facility or event.
For the module to “learn” a new format
and rate simply requires the momentary