Studio Technologies 5150 V.3 - Manual (Page 15)

Model 5150 User Guide Issue 1, June 2013
Studio Technologies, Inc. Page 15
Model 5150
Video Generator Module
The overlaid text provides support details
on how alternate custom images can be
created.
It’s expected that these pre-loaded images
will be replaced with application-specific
images. They can be easily created and
what they consist of is limited only by one’s
imagination. Refer to the Technical Notes
section of this guide for details.
Transitions between External
and Internal SDI Signals
Whenever a valid SDI signal is connected
to the selected Model 5150 input it will im-
mediately 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 SDI
input is subsequently removed. When
the Model 5150 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
5150’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 seven-second interval has elapsed the
internal generator will output either the
“720” or “1080” 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 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 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 sophisti-
cation. 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 consider-
ably shorter.
Output Format and Rate
When a valid signal is connected to the
SDI input it will be routed to the SDI out-
put 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 inter-
nally-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 con-
nection of an SDI signal that has the de-
sired format and rate. As long as the signal
is present on the SDI input for a minimum
of five seconds the Model 5150 will store
the “new” format and rate parameters in
nonvolatile memory. The module will then
use those parameters whenever the in-
ternal generator is active. The only caveat
for the module to “learn” a new format/rate