The Dual-Link DVI Repeater automatically compensates for signal degradation in long cables. Input cable length can be up to 50 feet (15 m), and the unit can drive long DVI cables on its output to 40 feet (12 m) by boosting the DVI video output.The DDC channel (for EDID and HDCP) can either be bypassed through the DVI repeater (source "sees" the connected LCD), or emulated, where the EDID is supplied from internal EDID memory in the repeater. When EDID is emulated, HDCP is turned off, forcing the source to send non-content protected video without HDCP. Using the learn button, users can copy and store EDID from any HDMI or DVI LCD into the internal EDID memory of the Dual-Link DVI Repeater.The unit is configured to buffer single-link DVI or HDMI signals. Using a pushbutton, its mode can be changed to support dual-link TMDS signals.The unit provides driver free USB 1.1 port connection to a PC. Free Windows™ PC software available on the website, allows reading, saving, manipulating, and writing EDID tables to and from the device. The EMX-DVI modes (Bypass vs. Emulate or Single-Link vs Dual-Link buffer) are also controllable via the USB port.When configured for Single Link extension, often the unit can operate from the power available through the DVI source signal and no external power supply connection is required. The unit ships with a universal power supply to use if the power through the DVI input is insufficient. The power can also come from the USB connector on a PC.The Emulated (internal) EDID data can be acquired from any connected LCD (using LEARN function), or a custom EDID file can be uploaded via the USB port. In addition to the above, the unit provides DVI-I bypass for analog RGBHV (or VGA) signals, so it can manage EDID for VGA sources and displays using inexpensive VGA to DVI cables or adapters.With the included software, you can read and save EDID data from any display.