Studio Technologies 230 2008 - Manual (Page 17)

Model 230 User Guide Issue 7, October 2008
Studio Technologies, Inc. Page 17
the external power source to be securely
attached to the Model 230.
As previously discussed in this user guide,
an IFB circuit or intercom line connected
to the Model 230 can serve as the unit’s
power source. Alternately, an external 24
volt DC source can be connected. For
redundancy, the IFB circuit, the intercom
line, and the external source can be con-
nected at the same time. If one of them
becomes inoperative, one of the remain-
ing sources can provide all Model 230
power.
The Model 230’s circuitry establishes the
priority in which the unit draws its oper-
ating power. If an external source of 24
volt DC power is connected, it will always
serve as the primary source. This mini-
mizes the impact that the unit’s power
draw could have on a connected IFB cir-
cuit or intercom line. If no external source
of 24 volt DC is connected and both an
IFB circuit and an intercom line is con-
nected, power will be drawn only from the
intercom line. This is because intercom
lines, by design, are better able to supply
power to devices such as the Model 230.
Multiple devices, such as intercom belt
packs, are expected to be connected to,
and powered by, a single intercom line.
IFB circuits are quite different, typically de-
signed to only supply a limited amount of
energy. This limitation can be compound-
ed by the fact that IFB circuits are often
distributed using very long cable “runs.”
So in conclusion, the Model 230’s power
draw priority was established so as to
minimize the chance that IFB circuit
performance would be impaired. And,
of course, no matter which source is pro-
viding power, audio signals from the IFB
circuit and intercom line can still serve
as headphone output audio sources.
Pushbutton Labeling
The three pushbutton switches used in
the Model 230 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
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, 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