The Decklink Duo 2 card has 4 SDI inputs/outputs and it is possible to configure the card as:
- 2 SDI inputs and 2 SDI outputs
- 4 SDI inputs
The configuration of the connectors is done in the Desktop Video application under Windows.

BNC connectors
When the card is configured for 4 SDI inputs the connectors are numbered as in the following picture:

This page was last updated on 2025-10-29