Studio Technologies 45DC - Manual (Page 8)

Issue 1, January 2015 Model 45DC User Guide
Page 8 Studio Technologies, Inc.
Audio Meters
The Model 45DC contains two sets of 5-
segment LED level meters. Each set of
two meters displays the level of the signals
being sent to and received from a party-line
interface channel. At the time of installa-
tion and setup the meters are invaluable in
helping to confirm correct operation. During
normal operation the meters offer rapid con-
firmation of audio signals flowing in to and
out of the unit. Additional LED indicators are
also provided on the front panel, offering a
status indication of the party-line DC power
sources, party-line activity status, and the
auto null functions. Two other LEDs offer a
direct indication of which source is powering
the Model 45DC.
Call Light Support
Typical single-channel party-line intercom
circuits provide a call light function by way
of a DC voltage applied to the audio path.
The Model 45DC can detect call light activ-
ity, convert it to a 20 kHz audio tone, and
transport the tone over the Dante audio
path. A Model 45DC unit at the “far end”
will detect the tone and re-generate the call
signal as a DC voltage on the audio path.
This allows full “end-to-end” call light sup-
port between two or more Model 45DC
units. It also allows a Model 45DC to send
and receive call light status with an intercon-
nected Model 45DR Dante to 2-Channel
Party-Line Intercom Interface. The Model
45DR is typically used with the RTS TW-
series of party-line user beltpacks including
the popular BP-325.
Ethernet Data, PoE, and DC
Power Source
The Model 45DC connects to a data net-
work using a standard 100 Mb/s twisted-pair
Ethernet interface. The physical intercon-
nection is made by way of a Neutrik®
etherCON RJ45 connector. While compat-
ible with standard RJ45 plugs, etherCON
allows a ruggedized, locking interconnec-
tion for harsh or high-reliability environ-
ments. The Model 45DC’s operating power
can be provided by way of the Ethernet
interface using the Power-over-Ethernet
(PoE) standard. This allows fast and ef-
ficient interconnection with the associated
data network. To support PoE power man-
agement, the Model 45DC’s PoE interface
reports to the power sourcing equipment
(PSE) that it is a class 3 (medium power)
device. The unit can also be powered
using an external source of 12 volts DC.
For redundancy, both power sources can
be connected simultaneously. An internal
switch-mode power supply ensures that all
Model 45DC features, including party-line
intercom circuit power, are available when
the unit is powered by either source. Four
LEDs on the back panel display the status
of the network connection, Dante interface,
and PoE power source.
Simple Installation
The Model 45DC uses standard connec-
tors to allow fast and convenient intercon-
nections. An Ethernet signal is connected
using a Neutrik etherCON RJ45. If Power-
over-Ethernet (PoE) is available operation
will commence immediately. An external
12 volt DC power source can also be con-
nected by way of a 4-pin XLR. Party-line
intercom connections are made using two
3-pin male XLR connectors. The Model
45DC is housed in a rugged yet lightweight
aluminum enclosure that is designed to be
“field tough.” It can be used as a stand-
alone portable unit, supporting what’s