Studio Technologies 220 2013 - Manual (Page 15)

Model 220 User Guide Issue 5, February 2013
Studio Technologies, Inc. Page 15
If both an IFB circuit and an external 24
volt DC source are connected, power will
be drawn only from the external source.
This minimizes the chance that lengthy
cable runs or other IFB circuit issues will
impact Model 220 operation. Whichever
device is providing power, audio signals
from the IFB circuit can still serve as the
audio sources for the headphone output.
Pushbutton Labeling
The three pushbutton switches used in the
Model 220 were selected for several rea-
sons. Foremost was the fact that they are
highly reliable, using gold-plated contacts
for long life in less-than-ideal environ-
ments. A second reason was that apply-
ing customized labels to the button caps
would be very simple. The labels, text
printed on clear material, are placed under
the clear caps on the top of the buttons.
From the factory the left button is labeled
COUGH, the center button is labeled
TALKBACK 1, and the right button is
labeled TALKBACK 2. This was selected
to be appropriate for many on-air applica-
tions in English-speaking locations. But
it’s expected that these may need to be
changed to meet the needs of specific
applications.
As a “head start” for some applications,
a clear sheet with a number of commonly
used button designations printed on it
is included in the shipping carton. These
were created at the factory using a stan-
dard personal computer graphics program
and laser printed onto 3M CG3300 trans-
parency film. The desired button labels
can be cut out with a pair of scissors or an
X-ACTO® knife following the printed guide
lines that indicate the required size.
The clear lens on top of each button cap
can be removed with a fingernail or small
screwdriver. Be certain not to scratch the
button if a screwdriver or other small tool
is used. The clear label can be removed
and replaced. The button cap is then
snapped back into the top of the button
housing using finger-pressure only. No
tool is required to replace the button cap.
If you need to make your own labels the
process is quite simple. Use a personal
computer to create the desired text. The
finished label size should be 0.625-inches
(15.8 mm) square. The completed artwork
can then be printed on transparency film
sheets using a laser or inkjet printer. These
sheets are readily available from most of-
fice supply stores. A pair of scissors or an
X-ACTO knife will complete the task.
Configuration
For the Model 220 to support the needs
of specific applications a number of op-
erating parameters must be configured.
These include microphone preamplifier
gain, phantom power on/off, headphone
source and output mode selection, and
operating modes. Four 8-position DIP
switch assemblies are used to establish
the desired configuration. These switch
assemblies are referred to as SW1 through
SW4, with individual switches designated
as SW1-1, SW1-2, etc. The switch assem-
blies are accessed through openings in
the bottom of the Model 220’s enclosure.
The enclosure does not have to be disas-
sembled to gain access to the switches.
To prevent unauthorized personnel from
changing the configuration settings, a
security plate is attached to the bottom