Artel DigiLink DLC170, Установка и эксплуатация

Страница: 15 / 50

DLC170 Function Modules Installation and Operations Manual 5
Understanding and Using the DLC170AD
Video Input
The DLC170AD accepts video signals through the 75 Ohm BNC connector located on the rear panel of the
module. This connector is the only source of analog video for the DLC170AD. When no video is available on
the selected input, the DLC170AD enables the standby video generator, which you can configure for one of
the following signal types:
• Grey screen at 525 lines (NTSC) or 625 lines (PAL) into which audio can be embedded
• Non-video keep-alive
Use the non-video keepalive signal to keep the optical link alive when an application requires that the standby
video generator not produce a detectable video signal (you cannot embed audio into the non-video
keepalive signal). Other function modules in the host chassis, such as the DLC103A, detect the keepalive
signal and signal that it is intentionally being sent across the optical link. Whenever the DLC170AD transmits
the grey screen or the non-video keepalive signal, the TX LED on the front panel illuminates yellow.
Audio Input
The DLC170AD accepts audio signals through a quad three-pin terminal block that consists of 12 pins. This
terminal accepts up to four balanced analog audio signal inputs, each with a positive (+), negative (-), and
ground (G) connector. The four balanced analog audio inputs are organized as two stereo pairs; left & right
channels. You terminate each input with either a nominal 600 Ohms or a high impedance input (see the
“Configuring Audio Termination with DIP Switch SW4” section on page 11 ).
The DLC170AD converts the analog signals to digital signals with 24-bit audio A/Ds sampling at a rate of
48 kHz. The digitized signals are then encoded into an AES-3 stream that the DLC170AD embeds into the
digital video in either 20-bit or 24-bit format.
An eight-position rotary switch allows you to set the A/D 0 dBFS level from +10 dBm to +24 dBm into
600 Ohms in 2 dB steps (see the “Configuring Peak Analog Audio Level with Rotary Switch SW6” section on
page 12 ). You can also use Artel’s element management system, DL Manager, to set the 0 dBFS level.
Electrical Output
The DLC170AD outputs a copy of the SDI electrical signal to the backplane for use by other modules in the
host chassis.
The front-panel monitor jack is a mini 75 Ohm SMB connector that allows you to monitor either the analog
composite video input or the DLC170AD SDI digital video output. When adjusting cable equalization, the
monitor jack provides a view of the analog video signal.
Optical Output
A single SFP socket on the DLC170AD provides the optical interface. Optical performance is dependant the
quality of your optical fiber and fiber interconnects, and on the selected SFP, which must be specifically
qualified by Artel to pass video signals. The SFP modules use LC/PC connectors. Consult Artel for available SFP
options.