Tait T855 User Manual

G2.2 T856/857 Optional Features M850-00
31/09/98 Copyright TEL
2.1.2 Typical Options
2.2 Line Transformer Inputs And Outputs
The line transformer (T210) is designed to provide a balanced interface to 600 ohm lines.
For normal operation the two centre connections (LINE I/P 2, LINE I/P 3) are shorted
together, and the 600 ohm line is connected between LINE I/P 1 and LINE I/P 4.
The secondary winding of the transformer is connected via 1k and 10Ω (R160) resistors
to pin 6 (AUDIO-2) of D-range 1 and may be used to monitor audio on the line. Pin 7 of
D-range 1 can be reconfigured as AUDIO-1 by removing R808 and R160, and placing
%R150 (refer to Section 2 in Part I for more details).
2.3 Opto Key
The keying circuitry may be completely isolated from the rest of the system by means of
the optocoupler (IC250) connected between pins 11 and 12 of the D-range connector. A
constant current source (Q270) allows keying voltages between 6 and 50V.
2.4 Relay Driver
A dedicated transistor (Q250) is provided for the purpose of switching an external (e.g.
coaxial) relay. The output is open collector and is activated by the Tx-Reg rail. This out-
put is available on pin 9 of the T800-03-0000 auxiliary D-range connector (D-range 2).
PL205 PL210 PL215 PL220
microphone pre-amp. compressed
and pre-emphasised;
line input pre-emphasised
(standard set-up)
[3-4]
B
[1-2]
L
[3-4]
H
[3-4]
E
microphone pre-amp. compressed
and pre-emphasised;
line input unprocessed
3-4
B
3-4
M
7-8
J
1-2
D
line and microphone compressed
and pre-emphasised
5-6
C
5-6
N
7-8
J
3-4
E
microphone pre-amp. compressed;
line and microphone flat response
3-4
B
3-4
M
3-4
H
5-6
F

Tait T855 Specifications

General

Brand	Tait
Model	T855
Category	Accessories
Language	English