Manual

Issue 3, August 2018 Model 44D User Guide
Page 8 Studio Technologies, Inc.
The GPI and GPO functions can be espe-
cially useful in party-line intercom applica-
tions where call-light signals are utilized.
Contact closures on matrix intercom sys-
tems can be “repeated” by Model 44D units
that are located anywhere within the associ-
ated local area network (LAN). The Model
44D is also directly compatible with the call-
light signal support provided by the Studio
Technologies’ Model 45DC and Model 45DR
Intercom Interface units. With a Model 44D
appropriately interconnected with a matrix
intercom system full call-light support can
be provided to and from RTS and Clear-
Com® party-line intercom circuits.
Pro Audio Quality
The Model 44D’s audio circuitry was de-
signed in the spirit of professional audio
equipment rather than that found in typi-
cal broadcast or commercial audio gear.
High-performance components are used
throughout, providing low-distortion, low-
noise, and high headroom. Care was taken
so that signal integrity is maintained in both
the analog and digital domains.
Audio Meters and Status LEDs
The Model 44D provides four 5-segment
LED meters. The meters, located on the
front panel, display the level of the audio
signals associated with the two line inputs
and two line outputs. At the time of installa-
tion and setup the meters are invaluable in
helping to confirm correct operation. Dur-
ing normal operation the meters offer direct
confirmation of the unit’s audio signal levels,
helping to ensure that optimal audio quality
is maintained. Additional LED indicators are
provided on the front panel, offering status
indications of the incoming power and gen-
eral purpose output (GPO) functions.
Tone Generator Mode
For special applications the Model 44D can
be configured to serve as a tone generator.
Instead of functioning as an audio interface
device, the Model 44D will generate two
sine-wave audio signals, one 18 kHz and
the other 20 kHz. These signals are avail-
able both as line-level analog and Dante
digital audio (transmitter) outputs. The 18
kHz tone is intended for use with matrix
intercom systems that are used with the
Studio Technologies’ Model 5422 Dante
Intercom Audio Engine. This tone will be
connected to a matrix intercom system
using either analog or Dante inputs. The
matrix intercom system will be configured
such that it will combine voice audio with
the 18 kHz tone to create specialized IFB
signals. These voice-with-tone signals will
be routed, by way of an audio transport
system, to Model 5422 interrupt inputs
associated with tone operated (TOX) IFB
channels. The Model 5422 will detect the
18 kHz tone and “trigger” the associated
IFB function. In this way high-performance
IFB functions can be implemented for REMI
(remote-production) applications.
The 20 kHz tone is provided for use in
applications where generation of in-band
signals that are compatible with the call
function on RTS TW-series party-line (PL)
intercom channels is desired. One example
would be for the 20 kHz tone to be con-
nected to an analog or Dante receiver (in-
put) channel on a matrix intercom system.
The intercom system would be configured
such that a button press on an intercom
“key” panel would cause 20 kHz to be sent
out an intercom channel. This would then
serve as a call “trigger” for devices such as
a Studio Technologies’ Model 391 Dante
Alerting Unit. Another interesting example