Studio Technologies 742A - Manual (Page 14)

Issue 1, July 2012 Model 742A User Guide
Page 14 Studio Technologies, Inc.
Audio Mixer
In the “pre +4” mode the monitor outputs
have a fixed nominal output level of +4 dBu.
The monitor outputs utilize ¼-inch 3-
conductor jacks for interconnection.
(Refer to Figure 6 for a detailed view.)
Prepare the mating connectors (plugs) so
the tip is signal high (+ or hot), ring is low
(– or cold), and sleeve is shield. To connect
to an unbalanced load connect tip to high
(+ or hot) and both ring and sleeve to
shield. Whether or not these outputs are
wired via a patch bay will depend on the
specific installation. In most cases they
will not be.
The reference tone direct output is elec-
tronically balanced, has a nominal +4 dBu
level, and is accessible via a ¼-inch 3-con-
ductor jack which is located on the back
panel. (Refer to Figure 7 for a detailed
view.) The output circuitry is capable of
driving a balanced or unbalanced load of
600 ohms or greater. Prepare the mating
plug so that tip is signal high (+ or hot),
ring is low (– or cold), and sleeve is shield.
To connect to an unbalanced load connect
tip to high (+ or hot) and both ring and
sleeve to shield.
Figure 7. Detail of back panel showing reference
tone direct output connector, associated level
trim pot, and headphone output jack
Figure 6. Detail of back panel
showing monitor output connectors
Reference Tone Direct Output
Direct access to a continuous source of
sine-wave reference tone is provided by
means of a line-level output. As one of
the unique features of the Model 742A, it
should definitely be utilized! This output
is intended to be connected to an au-
dio input associated with a audio/video
switcher’s “bars and tone” position. For
maximum flexibility, it is recommended
that this signal be routed via a patch bay.
In this way it can be easily accessed for
other test and calibration purposes.
A trim potentiometer, accessible from the
back panel, can be used to set the precise
level of the reference tone direct output.
After an installation has been completed it
may be desirable to set the trim pot to pro-
vide the required level. For details please
refer to the Post-Installation Calibration
section of this user guide.
Headphone Output
The Model 742A contains one headphone
output which is located on the back panel.
(Refer to Figure 7 for a detailed view.)
The output jack is a ¼-inch 3-conductor
(“stereo”) tip-ring-sleeve type. The audio