Wheatstone TV-80, Technical Manual

Page: 71 / 120

S T U D I O M O N I T O R
page 6 – 5
TV80 / Sep 98
Studio “On-Air” Tally Port
The SC-80 module tally port is activated by the console’s
mute control lines (see dipswitch “SW23”, preceding). Tally
signals are outputted at the module’s DB-9
“Tallies” connector, located at the top of the module’s rear
panel. There are two types of control signals available:
a) a simple relay closure with N.O., N.C. and tally common
pins (maximum current 50 milliamps at 24V), and
b) opto-isolated tally+ and tally– control pins (used to
power an ex5V tally lite/LED; maximum current
50 milliamps).
If you will be using a high powered lamp/bulb for the
external tally, you will need to provide an external power and
relay circuit that takes it control pulse from the SC-80 module’s
tally pins.
Studio Module Audio Wiring
All audio wiring for the studio monitor module is via two
DB-25 connectors mounted on the module’s rear panel (see
right). Audio signals include external line inputs (upper con-
nector “A”) and STUDIO and HDPN outputs (lower connec-
tor “B”). See pinout drawing on next page for wiring details.
Printed Circuit Board Load Sheets
Load sheet drawings, showing all part locations, are in the
Technical Drawings booklet (see “Chapter Contents” on page
6-1 for specific drawing locations).
Schematics
Schematic drawings are in the Technical Drawings book-
let (see “Chapter Contents” on page 6-1 for specific drawing
locations).
TALLY NO
TALLIES
(DB-9)
+5V DIG
TALLY COMMON
TALLY +
N/C
DIG COMMON
DIG COMMON
TALLY -
TALLY NC
T
A
L
L
I
E
S
I
O
I
O
A
B
SC-80 Module Rear
Panel Connectors