1. When two HDMI devices are connected together the EDID communication protocol automatically determines the highest resolution both devices support and then configures the HDMI link to that resolution. 

As the CHD 1802/CHD 1812 modules support video formats up to 1080P/60Hz then the SDI output will typically default to 1080P/60 (3Gbit/s SDI) as most HDMI devices support 1080P resolutions. 

If 3Gbit SDI signals are used in a standard 1.5GHz or 270Mbit SDI environment then no image will be visible, and the modules would appear not to be working. 

If 1.5Gbit or 270Mbit SDI output is required, then the HDMI source device should be manually set to output the desired video resolution. Alternatively, it is possible to use the yelloGUI application to force the CHD 1802/CHD 1812 into the desired video format. (As we do not have an internal scaler, this is done by limiting the formats the module supports over EDID so the sending device changes its HDMI resolution)

Introduction:  http://support.lynx-technik.com/support/solutions/articles/1000035681-forcing-a-permanent-output-format-with

The yelloGUI application can be downloaded by clicking the following link:


2. The HDMI content may have HDCP copy protection, in which case the HDMI present LED will be OUT and the module will block the conversion and provide a black SDI output.

Note: A lot of playback consumer devices impose hardware HDCP copy protection even if the source media is not copy protected. Please verify the operation of the yellobrik module on a HDMI source which is known not to have HDCP copy protection (e.g. most HDMI cameras) before contacting technical support.