Studio Technologies 5132 2014 - Manual (Page 13)

Model 5132 User Guide Issue 5, October 2014
Studio Technologies, Inc. Page 13
Model 5132
Party-Line Interface Module
have DC voltage present on them so en-
abling the Model 5132’s party-line interface
would not be possible. Mode 2 would allow
the audio interface channels to be fully
functional; the two line-level outputs would
be active and the audio null function can
be enabled.
Another example of where mode 2 would
be useful is when a Model 5132’s party-
line interface is connected to one or more
Studio Technologies’ Model 200-Series
announcer’s or producer’s consoles and
the consoles are being locally powered.
(Model 200-Series devices can be pow-
ered by way of a party-line intercom circuit
or by way of an external source of 24 volts
DC; the latter is preferred.) In the case of
a Model 200-Series device being locally
powered it would be a completely “valid”
connection to the Model 5132. Mode 2
would enable the line-level outputs and
allow audio null activation even though no
DC current is being drawn or DC voltage is
being provided to the Model 5132’s party-
line interface.
Level Meters
The four audio level meters on the Model
5132 are calibrated differently from typi-
cal “VU” meter scales. Their “steps” are
labeled in reference to the level of the
signals being sent to, and received from,
the party-line interface. The ballistics of
the meters is also different, being a cross
between VU and peak.
During operation the green 0 LEDs will
light in response to audio levels of –10 dBu
being present on the party-line intercom
channels. When a 5132S (SMPTE level)
module has its 0 LEDs lighting they cor-
respond to +4 dBu being present on its
associated line-level audio input or output
connections. In the case of a 5132E (EBU
level) module the audio input and output
level would be 0 dBu.
The four green LEDs of each meter in-
dicate that the levels are in the normal
range. The yellow LED lights when a signal
is approximately 6 or more dB above the
nominal (–10 dBu to or from the party-line
channel) level. Optimal signals will result in
the four green LEDs lighting almost solidly
with the yellow LED lighting only on peak
signals.
Internal Party-Line Power
Supply
If the Model 5132’s internal party-line inter-
com power source is enabled one or more
party-line user devices can be directly
connected and powered by the party-line
interface. The only restriction on the num-
ber of user devices that can be connected
is that the total current draw must be equal
to or less than 180 mA. Broadcast-stan-
dard devices such as the RTS BP325 are
directly compatible and will provide excel-
lent performance. Up to three of these
units can typically be supported.
For reference, this paragraph provides de-
tails on the signals that are present on the
party-line intercom interface’s 3-pin male
XLR connector. When the internal party-
line power supply is active pin 1 provides
common for power and audio; pin 2 has
both 28 volts DC and channel 1 audio;
pin 3 has channel 2 audio. The nominal
audio output level on the two channels is
–10 dBu, whether or not the module is a
5132S or a 5132E. The maximum current
draw from pin 2 to pin 1 is 180 mA. The
circuitry associated with pin 3 is protected
from damage should it accidentally be
interconnected to pin 2 (28 volts DC).