Studio Technologies 5152 V.2 - Manual (Page 24)

Issue 4, September 2013 Model 5152 User Guide
Page 24 Studio Technologies, Inc.
Model 5152
Video Generator/Audio Embedder Module
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 5152 detects that an SDI
input signal is no longer present the SDI
output switches to an image with a solid-gray
color. This color remains active for approxi-
mately seven seconds as 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
5152’s output can be terminated without
alerting viewers that anything is amiss. This
gray image can also be helpful as a marker
when editing recorded video. After the sev-
en-second interval has elapsed the inter-
nal generator will output either the “720” or
“1080” stored image.
It’s important to note that the Model 5152
does not perform a smooth transition when
switching between an external SDI source
and the internal SDI generator. 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 tran-
sition as the circuitry in the Model 5152 was
not designed to that level of sophistication.
This shouldn’t cause an operational issue as
the Model 5152 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 interrup-
tion will occur during transitions but typically
it will be considerably shorter.
Full-Time Video Generation
A configuration selection allows the Model
5152 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 whenev-
er a valid signal is connected to the select-
ed SDI input. But the SDI input source will
only serve as a timing reference. Its video
and related data (e.g., embedded audio) will
not pass through to the SDI output(s). The
custom 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 5152. 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
5152 to revise its parameters by following
the format and rate of the connected SDI
signal. This ensures that the Model 5152
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 connection
of an SDI signal that has the desired format
and rate. As long as the signal is present on
the selected SDI input for a minimum of five
seconds the Model 5152 will store the “new”
format and rate parameters in nonvolatile
memory. The module will then use those
parameters whenever the internal generator
is active. The only caveat for the module to
“learn” a new format/rate combination is that
it must be a compatible combination. Refer
to the Specifications section of this guide for
a complete list.