Studio Technologies 220 2004 - Manual (Page 38)

Model 220 User Guide Issue 2, August 2004
Studio Technologies, Inc. Page 39
arrangement allows muting to take place
without disturbing phantom-power that may
be enabled to support a condenser-type
microphone. The direct microphone output
card also contacts two 3-position header
connectors. These interface with “head-
ers” on the Model 220’s main printed circuit
board assembly, providing access to the
microphone input connector and auxiliary
relay contact.
The direct microphone output card kit
contains a printed circuit board assembly,
two interconnecting cables, and mounting
hardware. Installing the kit is very simple.
The card’s 3-pin male XLR-type connector
is mounted into one of the three spare con-
nector locations on the Model 220’s back
panel. Specifically, the connector location
that is closest to the microphone input con-
nector should be used. The two screws,
with associated locking nuts, are used
to secure the connector and associated
printed circuit board to the enclosure. The
interconnecting cables are then used to link
the card with the Model 220’s main printed
circuit board assembly. One end of the
first interconnecting cable is plugged into
the card’s 3-position header that is labeled
IN. The other end of this cable is plugged
into the 3-position header associated with
the microphone input connector, labeled
P5, located on the main printed circuit
board assembly. One end of the second
interconnecting cable is plugged into the
card’s header that is labeled RELAY. The
other end of this cable is plugged into the
header associated with the auxiliary relay,
labeled P9, located on the main printed
circuit board. Additional installation details
are provided in the Additional Connectors
section of the user guide. A recommend-ed
connector labeling method is also included.
After the direct microphone output card
has been installed, one configuration step
must also be performed. Using the con-
figuration switches, located on the bottom
of the Model 220’s enclosure, the auxiliary
relay control mode must be set to the
“follows main output status” position. This
provides the on/off (muting) control of the
direct microphone output signal. Should
the auxiliary relay’s configuration be left
in the “relay disabled” position, the direct
microphone output will always be in the
off (muted) state. It’s interesting to note
that the recommended auxiliary relay
configuration assumes that the direct
microphone output will be used in place
of the Model 220’s main output. However,
for other applications there is certainly no
reason why the direct microphone output
can’t be configured to follow the status of
one of the talkback buttons. Special situ-
ations may benefit from having a micro-
phone signal that is active only during
“talkback.”
Using the direct microphone output
is essentially the same as connecting
directly to a microphone. An interface
cable should be wired so that signal high
(+ or hot) is connected to pin 2, signal
low (– or cold) is connected to pin 3,
and shield is connected to pin 1. When
connecting a condenser microphone it’s
recommended that the Model 220 provide
the source of phantom power. In this way
the microphone will stay active whenever
the Model 220 is operating, even if the
connection made to the direct microphone
output is broken. By ensuring that the
microphone remains active, the talkback
functions will continue to operate correctly.
Several slight differences between con-
necting to a stand-alone microphone and