Studio Technologies 220 2013 - Manual (Page 40)

Issue 5, February 2013 Model 220 User Guide
Page 40 Studio Technologies, Inc.
the direct microphone output connector.
These resistors provide isolation, allowing
the direct microphone output to be muted
while still maintaining microphone audio
on the Model 220’s preamplifier input. This
audio is necessary so that the talkback
functions can continue to operate. The
series resistors will have minimal impact,
simply raising the microphone’s apparent
source impedance as “seen” by the exter-
nal preamplifier.
Remote Data Interface
For future applications the Model 220’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 220’s
microcontroller integrated circuit with a
remote switch/status display panel. Con-
tact Studio Technologies to find out the
implementation status of this function.