Studio Technologies 5121 - Manual (Page 8)

Issue 3, October 2014 Model 5121 User Guide
Page 8 Studio Technologies, Inc.
Model 5121
Line/IFB Output Module
For details on appropriate mating connec-
tors refer to Appendix A located at the end
of this document.
For connecting to balanced sources the
signal + (high), signal – (low), and common/
shield connections should be used. With
unbalanced sources connect signal high to
the Model 5121’s signal + (high) and signal
low to both the signal – (low) and common/
shield connections. Refer to Figure 2 for
details.
being installed. For Model 5121S (SMPTE)
version modules the nominal level should
be –20 dBFS. For Model 5121E (EBU) ver-
sion modules the nominal level should be
–18 dBFS.
DC Input and Data Bus
A 4-position header, located adjacent to
the analog audio input header, is used to
connect DC power and a local RS-485 se-
rial data bus to the Model 5121. Two pins
on the mating connector are used to con-
nect a source of nominal 12 volts DC. The
acceptable range is 10 to 18 volts DC with
a maximum current of 600 milliamperes
at 12 volts DC. For remote control opera-
tion two pins on the mating connector will
implement the data bus connection from a
Studio Technologies’ Model 5190 Remote
Access Module.
Like the analog audio inputs, the mating
connector is compatible with the AMP MTA
series of IDC receptacles. It is, however,
a 4-position rather than 5-position connec-
tor. For 22 AWG wire the closed-end-style
receptacle is AMP 3-643813-4; the feed-
through-style receptacle, used for busing
connections, is AMP 3-644540-4. The body
color for both receptacles is red, following
the convention of the MTA-100 series for
compatibility with 22 AWG wire. Refer to
Appendix A of this guide for additional con-
nector details.
1. – DC (Common)
2. + DC (10-18 volts)
3. + Data (RS-485)
4. – Data (RS-485)
Figure 3. DC Input and Data Bus Connections
Pin Number Function
1 Common/Shield
2 + CH1
3 – CH1
4 + CH2
5 – CH2
Figure 2. Analog Audio Inputs
Digital Audio Input
The Model 5121’s two audio input channels
can be supplied in the form of a
75 ohm unbalanced digital signal that is
compatible with the AES3 standard. The
physical connection is made by way of a DIN
1.0/2.3-compliant receptacle. This recep-
tacle is located adjacent to the analog audio
input connector. This type of signal and
connector is commonly used in broadcast
and related applications. It was specifically
selected for the Model 5121 because of its
small size.
The digital audio input signal is intended to
have a sample rate of 48 kHz, although the
less-common 32 kHz and 44.1 kHz are also
compatible. The recommended nominal level
of the connected digital audio source will
depend on the specific Model 5121 version