Studio Technologies 212 2013 - Manual (Page 33)

Model 212 User Guide Issue 5, May 2013
Studio Technologies, Inc. Page 33
this implementation, along with the recom-
mended LED, only 1 milliampere per LED
is consumed.
It’s intended that high-efficiency white
LEDs be installed. They use very little DC
current and have essentially infinite life.
The recommended LED is the Kingbright
WP7104QWC/D which as of the time of this
writing is available from sources such as
Digi-Key (www.digikey.com) and Mouser
Electronics (www. mouser.com).
The mating socket in each pushbutton
assembly is accessed by removing the
button’s lens caps, graphic label, and back
frosted lens. Once this is done installing the
LED should be very simple, requiring only
lead trimming and careful insertion. Begin
by removing the top clear lens, label, and
frosted under-lens in each pushbutton. Trim
the LED leads to 0.25 inches in length and
insert into the sockets with the cathode end
located nearest the front of the Model 212.
Power up the Model 212 and observe if the
LEDs light. They are polarity sensitive and if
either or both do not, remove the offending
LED(s), rotate them 180 degrees, and then
re-insert.
Remote Control Input
Connections
Provision has been made on the Model
212’s printed circuit board assembly to
allow external switches or contact closures
to control the main output and talkback out-
put functions. A 3-position header, labeled
P17, provides access to the circuitry associ-
ated with the functions. Pin 1 of the header
is connected to the common point of the
Model 212’s circuitry. Pin 2 of the header
is connected to the circuitry associated with
main output pushbutton. Pin 3 of the head-
er is connected to the circuitry associated
with the talkback output pushbutton.
The input circuitry is “active low,” with a
10 k ohm resistor connected to +5 volts act-
ing as a pull up. A combination of resistors
and capacitors provides ESD protection. A
qualified technician can use these inputs for
special applications. Contact the factory for
additional details.
Digital Audio Outputs
As has been previously discussed in this
user guide, the Model 212 is capable of sup-
porting three digital audio outputs. Directly
accessible on the back panel are the BNC
connectors for the AES3id output and the bi-
directional interface. Accessible internally for
installer-selected applications is the AES3
output. It’s important to mention that these
three outputs are always active, each send-
ing out the identical digital audio and control
bit stream. While most applications will use
only one of the outputs, there’s no reason
why two, or all three, can’t be utilized.
In addition, while the bidirectional digital
interface is intended to send and receive
data over a single cable, it can be used as
a standard AES3id output. The only require-
ment is that the configuration for the digital
input source must be selected for something
other than the bidirectional digital interface.
This ensures that a stable clock source will
be available for the all the digital outputs.
Remote Data Interface
For future applications the Model 212’s main
circuit board provides a bi-directional data
interface connection. It complies with the
RS-485 standard and operates at a data rate
of 115.2 kbps. It is expected that the data
interface will link the Model 212’s micro-
controller integrated circuit with a remote
switch/status display panel. Contact Studio
Technologies to find out the implementation
status of this function.