Model 233 User Guide Issue 1, September 2007
Studio Technologies, Inc. Page 11
Configuration
Model 233 configurations are made using
a number of DIP-type switches and four
trim potentiometers. One 8-position switch
array is used to set the gain of the micro-
phone preamplifier, the on/off status of
phantom power, and control of the head-
phone output mode. A 12-position switch
array configures which of the four cue
audio sources, as well as the sidetone au-
dio, are routed to the headphone outputs.
In addition, the last two sections of the
12-position switch array are used to se-
lect whether talkback audio will be routed
to the intercom interface. Two 8-position
switch arrays communicate the desired
operating modes to the microprocessor.
Two rotary “trim pots” are used to adjust
the sensitivity of the line inputs. Two ad-
ditional rotary trim pots are provided to
adjust the sidetone (null) level for the inter-
com interface’s talkback functions.
All switches and trim pots are accessible
via the bottom of the Model 233’s enclo-
sure; the unit does not have to be disas-
sembled. Changes made to any of the
configuration parameters become active
immediately. To prevent access to the
configuration controls a security panel,
included with each unit, is attached to the
bottom of the enclosure.
Connectors
The Model 233 uses standard connectors
throughout. The microphone input, line
inputs, and intercom interface functions
use 3-pin female XLR-type connectors.
The main and line-level talkback output
functions use 3-pin male XLR connectors.
The headphone output utilizes a ¼-inch
3-conductor jack. The external source of
24 volt DC power is connected by way of a
2.1 x 5.5 mm “locking” coaxial power jack.
Additional Connector Locations
In the world of broadcast, production, and
public address audio it’s fair to say that
applications vary widely. To this end, up to
three additional XLR-type connectors can
be easily mounted into the Model 233’s
back panel. Multiple 3-position “headers”
located on the Model 233’s circuit board
provide technician-access to literally every
input and output connection. In addition,
some additional features, including the
remote control inputs and tally output, are
accessible using 3-position headers. Using
a factory-available interface cable kit, these
headers allow a Model 233 to be optimized
to meet the exact needs of specific applica-
tions. For example, some applications may
prefer to use a multi-pin XLR-type connec-
tor to interface with a headset. This could
be easily accomplished by adding the
appropriate 6- or 7-pin XLR-type connec-
tor and making a few simple connections.
Other applications may benefit from hav-
ing “mult” or “loop-through” connections,
something easily incorporated into a
Model 233.
Multi-Pin Headset Connectors
As previously mentioned, some applica-
tions are best supported using headsets
that interface using a multi-pin connector.
In most of these cases the desired connec-
tors are 6- or 7-pin male XLR-type wired to
an industry-standard pin-out scheme. Stu-
dio Technologies offers headset connector
assemblies that allow fast and painless in-
stallation into a spare connector location in
the Model 233’s back panel. Details about
these optional assemblies are available on
the Studio Technologies website.