Studio Technologies 220 2004 - Manual (Page 14)

Model 220 User Guide Issue 2, August 2004
Studio Technologies, Inc. Page 15
power will be drawn only from the exter-
nal 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 head-
phone output.
Pushbutton Labeling
The three pushbutton switches used in
the Model 220 were selected for several
reasons. Foremost was the fact that they
are highly reliable, using gold-plated con-
tacts for long life in less-than-ideal environ-
ments. A second reason was that applying
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 ap-
plications.
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, fol-
lowing 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 selection, and operating modes.
Four 8-position DIP-type switch assem-
blies 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 assemblies are ac-
cessed through openings in the bottom of
the Model 220’s enclosure. The enclosure
does not have to be disassembled
to gain access to the switches.
To prevent unauthorized personnel from
changing the configuration settings, a
security plate is attached to the bottom
of the Model 220’s enclosure. For conve-
nience, attached to the security plate is
a configuration settings label. It provides
a summary of the configurable parameters