Remote control inputs, Connecting the model 76da to the model 77 – Studio Technologies 76DA V.4.12 User Manual
Page 14
Issue 9, May 2014
Model 76DA/77 User Guide
Page 14
Studio Technologies, Inc.
for Surround
signal connected to the Model 76DA is be-
ing connected (“multed”) to other inputs it
may be desirable for the termination to be
disabled. A general “rule of thumb” is that
termination should be applied only at the
location of the last physical device using a
sync signal.
Remote Control Inputs
Support is provided for two remote control
input functions: remote mute all and re-
mote dim. These functions only impact the
post-fader surround and stereo digital and
analog monitor outputs. The Model 76DA’s
inputs use logic gates, “pulled up” to 5 volts
DC by way of resistors, which are active
whenever they are brought to their logic
low state. Inputs of this type are commonly
referred to as GPI inputs. While the input
circuitry is protected from over-current and
static discharge (ESD), care should be
taken to prevent nasty signals from reach-
ing them. The inputs are active only when
held in the low state; they can’t be config-
ured to change state (“latch”) in response
to a logic pulse.
A 9-pin female D-subminiature connector
is used for the remote control inputs. Refer
to Figure 6 or Appendix A for the exact
connection details. Note that pin 4 (remote
common) connects to the Model 76DA’s
internal circuit common connection as well
as to the Model 76DA’s chassis and mains
earth connections. Figure 6 also shows
two spare remote control inputs (pins 8
and 9). These are provided for future ap-
plications and should remain unconnected.
This connector also allows access to an
RS-485 data interface. This interface is
not supported in the Model 76DA and, as
such, pins 7 and 2 should remain untermi-
nated.
Connecting the Model 76DA
to the Model 77
A 9-pin female D-subminiature connector,
labeled To/From Control Consoles, is pro-
vided on the back panel of the Model 76DA
Central Controller. This is used to interface
the unit with Model 77 Control Consoles.
Refer to Figure 7 or Appendix A for details.
A 9-pin female D-sub connector, labeled
To/From Central Controller, is provided on
the back panel of each Model 77 Control
Console. A cable with 9-pin male D-sub
(DE-9M) connectors on each end is
used to interconnect the Model 76DA with
the Model 77 units. A cable is included in
the shipping carton. The cable implements
all nine connector pins in a one-to-one
manner.
Should an interconnecting cable of a differ-
ent length be required there’s no problem
for one to be fabricated and used. While it
can be wired in a one-to-one fashion sup-
porting all nine pins, only four connections
are required: pin 1 (data +), pin 6 (data –),
pin 4 (DC +), and pin 9 (DC –). The Model
76DA’s connector pin-out scheme was de-
Signal
Pin
Direction
Data + (RS-485/RS-422)
7
Not used
Data – (RS-485/RS-422)
2
Not used
Data Shield
1
Shield
Remote Mute All
5
Input
Remote Dim
6
Input
Remote Spare 1
8
Input
Remote Spare 2
9
Input
Remote Common
4
Common
Note: Connector type on Model 76DA is 9-pin female
D-subminiature (DE-9F). Connector uses 4-40
threaded inserts for locking with mating plug.
Figure 6. Connections for Remote Control
Inputs