ASTEL TTM 101C Operating Instructions Manual
Text of the manual
Principle of operation..................................................................................................................................3
Controls and connectors.............................................................................................................................4
Connections................................................................................................................................................5
Installation...................................................................................................................................................5
Appearance ................................................................................................................................................6
Specifications..............................................................................................................................................6
This unit is produced to comply with Directive
89/336/EEC.
The video twisted-pair transmitter TTM 101C is a
correction
amplifier
with
the
standard
asymmetrical video input and symmetrical output
which is adjusted to connect the twisted-pair
cable. It has very small dimensions and very low
power consumption. The choice of output
impedance allows the use of different kinds of
cables.
FEATURES
very small dimensions
simple installation
AC/DC power supply
very low power consumption
over-voltage protection
dual output impedance
pre-emphasis +10 dB / 5 MHz
BLOCK DIAGRAM
PRINCIPLE OF OPERATION
The input is closed with the impedance of 75 .
Then follows the stage which defines the pre-
emphasis. By means of the amplifier stage two
signals separated by 180 appear on the output A
and B.
The output impedance jumper enables a choice of
output impedance - 125 or 90 .
The power is supplied by connecting to the AC or
DC power supply unit.
CONTROLS AND CONNECTORS
FRONT VIEW
1
(1) VIDEO INPUT
BNC video input connector with 0.5 m of RG-59
cable to connect the TTM 101C to the video
camera.
REAR VIEW
(1) JUMPER J2
Jumper to select the output impedance. When the
jumper is removed the impedance is 125 ohm.
(2) JUMPER J1
Jumper to activate the pre-emphasis when the
TTM 101C is used for long distance transmission.
When the jumper is removed the pre-emphasis is
inactive.
(3) AC/DC POWER SUPPLY
Terminal block to connect the AC or DC power
supply from 12V to 24V.
(4) TWISTED-PAIR OUTPUT
Terminal block to connect the twisted-pair cable.
Be sure to switch-off the power supply unit
before connecting to other equipment.
Also refer to the instruction manual of the
equipment to be connected.
VIDEO
TWISTED-PAIR
RECEIVER
MON
CAM
POWER
SUPPLY
INSTALLATION
(1) Remove the jumper J1. (0 dB)
(2) Insert or remove the jumper J2 to set the correct cable impedance.
(125 ohm for PE or PAPER, 90 ohm for PVC cable insulation)
(3) Connect the power supply unit. (AC or DC)
(4) Connect the video test generator (1 Vpp / 75 ) to the video input connector.
(5) Switch-on the power supply unit.
(6) Switch-on the video test generator.
(7) Check the positive video output signal between A and (casing).
(8) Check the negative video output signal between B and (casing).
(9) Switch-off the power supply unit.
(10) Switch-off the video test generator.
(11) Disconnect the video test generator.
(12) Connect the twisted-pair cable to the terminal block connector.
(13) Connect the video source (video camera) to the video input connector.
