Manual

Model 44D User Guide Issue 3, August 2018
Studio Technologies, Inc. Page 7
The Model 44D’s tone generator mode
enables the unit to create 18 kHz and
20 kHz analog and digital sine-wave audio
signals. The 18 kHz tone is provided as
a resource when supporting remote-
production (REMI) applications that use
the Studio Technologies’ Model 5422
Dante Intercom Audio Engine. The tone
can be used by a matrix intercom system
to facilitate creation of voice-with-tone
interruptible foldback (IFB) signals. When
routed to the Model 5422’s interrupt inputs
these specialized IFB signals will allow ex-
cellent talent cueing performance to occur.
The 20 kHz tone is provided for use in
applications where generation of a party-
line call signal is desired. For example, the
20 kHz tone can be connected to a matrix
intercom system which would be config-
ured such that a button press will cause
20 kHz to be sent out an intercom chan-
nel. This can serve as a “trigger” signal for
visual or audible alerting devices, such as
the Studio Technologies’ Model 391 Dante
Alerting Unit.
Line Inputs
The Model 44D provides two analog
line-level input channels. A configuration
choice allows the nominal level of the
input signals to be +4 or 0 dBu. When
configured for +4 dBu the unit will be
compatible with SMPTE applications
where the nominal digital signal level is
–20 dBFS. In the 0 dBu configuration the
line inputs are optimized for EBU applica-
tions where the nominal digital signal level
is –18 dBFS.
The electronically balanced (differential)
input circuits are capacitor-coupled and
ESD (static) protected for reliable opera-
tion in a variety of applications. They are
also protected from damage should a
moderate DC voltage be accidentally con-
nected. Sources can include analog I/O
cards on matrix intercom systems, audio
consoles, wireless microphone receivers,
and broadcast routers.
Line Outputs
The Model 44D provides two analog line-
level output channels. As with the line
inputs, a configuration choice allows the
nominal level of the output signals to be
+4 or 0 dBu. This allows compatibility in
applications where SMPTE (+4 dBu =
–20 dBFS) or EBU (0 dBu = –18 dBFS)
standards may apply. The outputs are
electronically balanced, capacitor-coupled
and ESD (static) protected. The outputs
are compatible with virtually all balanced
and unbalanced inputs with an impedance
of 2 k ohms or greater.
General Purpose Inputs and
Outputs
The Model 44D allows the sending and
receiving of status signals using high-
frequency audio tones that are included
with within the Dante audio channels.
When two Model 44D units are intercon-
nected using an Ethernet network and
Dante, two status signals will be trans-
ported in each direction. Each general
purpose input (GPI) is compatible with
contact closures provided by equipment
such as matrix intercom systems or rout-
ers. A closure on a GPI on one Model 44D
unit will result in the closing (shorting) of a
solid-state relay contact on the other Mod-
el 44D. To assist in implementing special-
ized GPI and GPO applications a source
of low-current DC power is also provided.