Tascam AV-452 Installation & Support Manual - 5 – Rear Panel Connections
5 – Rear panel connections
TASCAM AV-452
Installation & Support Guide
15
Note the following levels and input impedances, cor-
responding to the different connectors on the barrier
strip:
The level of the intercom signal is set as explained
below, and a squelch circuit is also available
d
. The
intercom signal is enabled and disabled using the
front panel
INTERCOM
key
G
.
c
AV DUCKER RATIO and THRESH
controls
These trimmer pots are used if the AV
ducking facility is enabled using the DIP switches
(see "Customization and settings" on page 16). If this
facility is not enabled, these controls have no effect.
If this is enabled, the amount by which the currently-
selected AV signal is ducked is set between –6 and
–20 dB, depending on the position of the
RATIO
trimmer pot. Turn this pot clockwise to increase the
amount that the AV signal is dimmed.
The
THRESH
trimmer pot adjusts the threshold level
of the microphone signal at which the ducking facil-
ity operates. Turn this pot clockwise to increase this
trigger level.
d
LEVEL and GATE THRESH controls
These two trimmer pots are used with the
INTERCOM
signals input at
b
.
The
LEVEL
control adjusts the level of the intercom
signal fed to the mix (post-
ROOM LEVEL
). Turn this
clockwise to increase the level of the signal.
The
GATE THRESH
squelch control is used to con-
trol the threshold of a noise gate, which opens when
the level of the intercom signal exceeds this level.
This allows an otherwise slightly noisy intercom to
be connected without interfering with the other
signals.
e
LINE OUTPUT mode switch
This switch
allows the line output
X
of the AV-452 to act as two
mono line sources, driving auxiliary amplifiers, etc.
in two locations, or it allows it to act as a stereo am-
plifier, driving another stereo unit.
External control connectors
There are two D-sub connectors, used for external
control of the AV-452.
The details relating to these connectors are described
in "External control" on page 18.
f
RS-232 serial port
This female 9-pin D-
sub port accepts and receives serial signals, allowing
the AV-452 to be controlled by a serial device. See
the document Serial Protocol Reference (available on
request from your TASCAM dealer or distributor) for
full details of the format and content of the serial
commands and messages.
NOTE
Although the connector is marked
RS-232
, it can be
used for RS-422 and RS-485 serial data interchange as
well as for RS-232 format data.
g
RELAY CONTROL connector
This
female 37-pin D-sub connector accepts commands
and transmits tally signals. It also can be used to con-
nect a wired IR “blaster “ transmitter for the control
of other devices, such as a video projector or monitor.
h
SERIAL ADDRESS selector
Use this to
select the serial address (
0
through
9
) of the AV-452
when controlling it using RS-485 commands.
i
CUSTOMIZE DIP switches
See the fol-
lowing section for the meanings of these configura-
tion switches.
Connector
Level, input impedance
70V
70 V, 40 k
Ω
24V
24 V, 12 k
Ω
12V
12 V, 4.7 k
Ω
f
g
3 4 5 6
1 2
ON
DIP
0
1
2
3
4
5
6
7
8
9
h
i