Studio Technologies 212 2013 - Manual (Page 30)

Issue 5, May 2013 Model 212 User Guide
Page 30 Studio Technologies, Inc.
a nominal input impedance of 10 k ohms.
Capacitors in series with the transformer’s
primary provide protection again acciden-
tal connection to a signal that has DC volt-
age present on it. The nominal input level
is +4 dBu but should work correctly with
signal levels down to nominal –10 dBu.
Note that if one or two line input cards
are installed in a Model 212, both analog
line-level audio signals and a digital audio
circuit can be connected at the same time.
The audio sources will be routed to the
headphone outputs by way of the head-
phone source configuration switches. Each
of the four possible audio sources can be
routed to the left-headphone output, the
right-headphone output, or both head-
phone-output channels. Details on how
to use these switches are provided in the
Configuration section of this user guide.
Connecting to the Analog
Outputs
The Model 212’s circuitry provides unbal-
anced line-level outputs associated with
the main and talkback outputs. These are
accessible using two 3-pin header connec-
tors located on the printed circuit board
assembly. The analog outputs are intended
for use in applications where it would be
beneficial to have, in addition to the digital
output resources, signals to interface with
the still-popular “analog world.”
Technically the main and talkback analog
outputs are capacitor coupled and have a
nominal level of -2 dBu. They can be used
directly, by way of optional connectors that
would be mounted in the unit’s back panel.
This is not optimal as the Model 212’s
common connection will “leave” the unit
and possibly be part of the ground hum
or noise situation. A line output card kit,
available from Studio Technologies, will
provide a transformer-coupled output. One
or two of the cards can be mounted into
the spare connector locations that are pro-
vided on the Model 212’s back panel.
A line output card kit contains a printed
circuit board assembly, the required inter-
connecting cable, and hardware. To install
the kit is very simple. The XLR connector is
mounted into one of the spare connector
locations on the Model 212’s back panel.
This secures the connector and associated
printed circuit board to the enclosure. The
interconnecting cable is then used to link
the card with the Model 212’s main printed
circuit board assembly. Refer to the next
paragraph in the section of the user guide
for details on which specific connectors
on the main printed circuit board assem-
bly apply to the main and talkback analog
outputs.
Additional Connectors
Two spare connector locations are pro-
vided on the Model 212’s back panel. From
the factory they contain blank plates that
can be readily removed and replaced
with a variety of XLR connectors. These
spare connector locations are specifically
included so that a Model 212 can be cus-
tomized to meet the many specific needs
that arise in broadcast and related audio
applications. Expected uses for these
locations include adding a 5-, 6-, or 7-pin
XLR connector to allow direct connection
of a broadcast headset. In addition,
Studio Technologies offers optional line
input cards that mount directly in a spare
connector location. This was previously
described in this user guide.
The spare connector locations are
compatible with the Neutrik DL-series of
connectors. For flexibility, versions are