Studio Technologies 220 2004 - Manual (Page 32)

Model 220 User Guide Issue 2, August 2004
Studio Technologies, Inc. Page 33
LED Colors
As previously described, two LED indica-
tors are associated with the main output
and are located directly above the main
output pushbutton switch. The red LED,
located on the left, is lit whenever the
main output is muted. The green LED,
located on the right, is lit whenever the
main output is active. The thought pro-
cess behind the color choices was that
red would relate to the main output being
muted (“stop”) while green would relate
to the main output being active (“go”). It’s
possible that these color choices may not
meet the needs of all users and applica-
tions. For example, it’s reported that one
European broadcaster typically uses these
two colors in the opposite fashion. Their
choice is to have the red LED lit whenever
the main output is active, warning the tal-
ent that they are “on-air.” The green LED is
lit whenever the main output is muted, in-
dicating to the talent that it’s “safe” to say
whatever they wish, about whomever they
wish to say it about!
For consistency, the LED associated with
each talkback button was selected to be
green. They light whenever their associ-
ated talkback output is active. It’s possible
that some applications may benefit from
revising these LED colors too. While red is
certainly one possible choice, other col-
ors are also a possibility including amber,
orange, or blue—these days there are lots
of choices available. The only limitation is
the amount of current available to light
each LED. Using series resistors of no less
than 560 ohms will ensure correct Model
220 operation.
A qualified technician can easily revise the
LED colors to meet an application’s exact
needs. The process would begin by disas-
sembling the Model 220’s enclosure and
detaching the pushbutton/LED printed cir-
cuit board assembly. The LEDs would then
be unsoldered, removed, and reinstalled
(or replaced) in the desired locations. To
control the LED current and set the bright-
ness, a resistor is electrically in series with
each LED. An 820 ohm, ¼-watt resistor is
associated with the red LED while a 560
ohm, ¼-watt resistor is associated with
each green LED. These resistors would
also have to be unsoldered, removed, and
reinstalled. Then the unit would be reas-
sembled and tested to confirm that the
changes function as desired.
For additional information about chang-
ing the LED colors, please contact Studio
Technologies technical support.
Travel Case
For portable applications it may be desir-
able to store and transport each Model
220 in a protective case. After much travel
with prototype announcer console units,
Studio Technologies’ personnel learned
to appreciate the Pelican Model 1450
case. Purchased with the foam interior
option, it does an excellent job of holding
one Model 220, its associated 24 volt DC
power supply, and documentation. Some
applications may benefit from selecting a
larger case that would also hold a related
headset, cables, etc. A larger case could
also be selected that would hold multiple
Model 220 units. Pelican sells their prod-
ucts through a dealer network, many of
which can be located via a web search.
Connecting Line-Level Audio
to the IFB Input
In “emergency” situations it’s possible to
connect line-level audio signals directly
to the Model 220’s IFB input connector.
This can be successfully done as long as