The DLC170DA converts optically received SDI to composite analog video (NTSC or PAL) and analog or AES audio. Used with the DLC170AD, the design insures full TV-1 RS250-C “short haul” analog performance over a true SMPTE 259M SD-SDI optical transport link. Additionally, it can be used as an optical receiver for all digital signals from 19.39 ATSC to 1.485Gb/s HD-SDI making the DLC170DA ideal for the eventual conversion from analog to digital video transport.

This innovative DigiLink module uses advanced video and audio processing for exceptional quality conversion of SDI (SMPTE 259M) to composite video and analog audio. It accepts a 270Mb/s 525/625 line SDI input from either the optical SFP receiver or the backplane, then converts it to composite analog and audio signals.

The received optical signal can be directed to the backplane for additional channel groups to be processed by other cards in the DigiLink chassis. Audio embedded per SMPTE 272M levels A, B, and C can be extracted as either four balanced analog audio channels or two stereo AES digital audio streams.

A front panel video monitor with analog or digital selector switch allows the incoming digital (with embedded audio) or composite analog output to be monitored using conventional digital/analog video equipment.

The DLC170DA is easily configured and managed via DigiLink’s DL-Manager Element Management System.

SDI-to-Analog Video Conversion (6)

Output format
SMPTE-170M NTSC-M or ITU-R BT.624-4 PAL-B/G composite video
Output amplitude
1.0 V p-p nominal
Output impedance
Output return loss (0 to 5.5 MHz)
>30 dB, 75ohm
Freq amplitude response
NTSC to 4.5 MHz <0.10 dB
NTSC to 5.0 MHz <0.10 dB
PAL to 5.5 MHz <0.10 dB
PAL to 6.0 MHz <0.10 dB
Differential gain
Differential phase
<0.7 degrees
Line time distortion
Chroma-luma gain
Chroma-luma delay
Signal to noise, weighted
>67 dB

SDI Audio-to-Analog Audio Conversion (6)

Output signal
Balanced Analog (1)
Output impedance
< 50ohm (2)
Nominal (test) level
18 dBm (3)
Maximum level (clip)
+10 to +24 dBm (4)
Insertion gain
±0.25 dB (5)
Freq amplitude response (20 Hz to 20 kHz)
±0.3 dB
THD+N (20-20k @ +18 dBm)
SNR (weighted)
>95 dBA
Crosstalk @10kHz
70 dB
Audio to video lead/lag
<2 ms
(1) Specifications are with 48 kHz, 24-bit audio.
(2) Designed to drive 600ohm loads.
(3) Nominal level is +20 dBm for 0 dBFS (clipping) with performance specifications based on a +18 dBm test level.
(4) User selectable maximum (0 dBFS) level in eight 2 dB steps.
(5) Each end set to the same nominal 0 dBFS level.
(6) Analog specifications based on end-to-end performance with DLC170AD


Input/output bit rate
Output jitter
I/O connectors
BNC female / 75ohm
I/O levels conforms to SMPTE
(1) Specifications are with 48 kHz, 24-bit audio SMPTE 272M-C embedded audio.

AES Audio Output

Output signal
Balanced digital (1)
Output format
AES3-2003 compliant
Output impedance


Ambient operating temperature
0 to 50°C
Ambient storage temperature
-40 to 80°C
Relative humidity
10 to 95% (non-condensing)
Power dissipation
9 Watts


0.8” x 5” x 10.8”
1 slot in DigiLink video platform chassis

Optical Interface

SPF Options
See SFP Specification

Regulatory Conformance

NEBS Level 3, CSA 60950, EN60950, EN55022 FCC Part 15 (Class A),CISPR 22

Single card SDI to composite video and analog audio conversion with optical receiver/repeater Convert SDI (SMPTE 259M) to composite video

  • NTSC or PAL
  • Analog composite 75ohm video output BNC
  • 10-bit component digital 525/625 line to NTSC-M or PAL-B/G conversion
  • Composite 12-bit processing

Convert SDI to analog or AES audio

  • SMPTE 272M-ABC audio de-embedding with 24-bit audio conversion
  • Balanced analog audio outputs (4)
  • Balanced AES audio outputs (2)

Optical transport of:

  • Analog video and audio
  • 1.485Gb/s HD-SDI (SMPTE 292M)
  • 270Mb/s
    • SD-SDI (SMPTE 259M-C, ITU 656)
    • SDTI (SMPTE 305M)
    • DVB-ASI
    • Artel 270

Optical to optical repeater Externally accessible SFP transceiver optics

  • Optical budget to 33dB
  • WDM (1310nm, 1550nm)
  • CWDM ITU G.694.2 (Channels 27-61)

Interoperation with

  • Other DigiLink modules
  • DigiLink 1220 /2701
  • Other non-scrambled or non-dithered SDI optical transmitters and receivers

Multiple monitoring options

  • Front panel monitor (mini 75ohm SMB) selectable between:
    • NTSC or PAL (post-conversion)
    • SDI (pre-conversion)
  • Front and rear panel status LEDs

Remote management via DL-Manager

  • No external software required
  • HTTP or SNMPv2
  • Monitor
  • Configure
  • Upgrade firmware

Quick Start Guide