2 Installation
digital
Revision C • 1/04
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LOGIC CONNECTIONS
BMX
digital modules have built-in logic I/O in-
terfaces that can control, or be controlled by,
peripheral devices connected to the console. For
example, a CD player connected to a module can
be automatically started when the module is
turned on. Then, at the end of the cut, the CD
Player logic can turn the module audio off and
control the off button illumination to indicate that
the cut has been played.
When a mic remote control panel is connected,
its On, Off, Cough and Talkback buttons control
the module while tally outputs from the module
control the button tallies on the mic panel.
BMX
digital modules have the following logic
connectors:
• Universal Input modules have two MAIN
connectors for the devices connected to the
A and the B inputs and two T/B OPTION
connectors for separate talkback control for
the A and B mic inputs.
• Telco/Codec and RLS modules have a
single LOGIC I/O connector for the device
connected to the module.
• The Session module has three EXT TIMER
connectors for resetting studio or producer
timers, a DATA (RJ-45) connector for con-
necting the console to a local LAN and the
connectors for the factory-installed wiring
that ties the mainframe to the meter panel.
• The Control Room module has a LOGIC
connector for the warning light, mute, dim,
and talkback. A CUE CNTL connector al-
lows external cue input control.
• The optional Studio module has two
LOGIC connectors for dim, mute, and warn-
ing indications and two talkback connec-
tors (PRODUCER and EXTERNAL).
• The Output 1 module has a PRODUCER
IFB LOGIC connector.
An unbalanced-to-balanced line transformer can
also be used to interface an S/PDIF signal.
Note 1:
A signal conversion interface must be
used to connect an AES/EBU output to a S/PDIF
input.
Note 2:
Some S/PDIF signals may not work with
the BMX
digital’s inputs, even with the additional
load resistor or a transformer, because of nonstand-
ard levels or protocols in the S/PDIF product.
DIGITAL CLOCK REFERENCE
The BMX
digital has an internal clock for sample
rate timing, with sample rate converters on each
input to synchronize/convert external digital sig-
nals to the console’s internal 48 kHz sample rate.
The console can synchronize to an external AES-
3 digital reference signal (of 48 kHz, ±100 ppm
only) when using the optional Ext. Input DSP card
(99-1356-1). A 3-pin connector on the card has a
green LED next to it to indicate whether the in-
ternal or external reference is active. When a valid
external reference signal is present, the LED is
off. If the LED is still lit with an external signal
connected, it indicates the reference signal is not
present or is out of range.
Connecting an S/PDIF Device to
a BMX
digital
AES/EBU Input
249 ohm resistor
From
S/PDIF
Device
Console
AES/EBU
Input
Signal
Shield
3
2
1
DSP Card Features
Thumbscrews
Heartbeat LED —
Flashes to indicate the
DSP is good.
External Input and LED —When
unlit, indicates the console is
using the External reference.
(optional connection)
