Abstract: The present invention is a device for converting an input signal of various formats to NRZ format in a user-selectable format with automatic self-testing, that includes at least one first channel, where each first channel includes a comparator, an activity detector, an inverter, and a driver circuit, where the comparator is configured for different signal types; at least one second channel, where each second channel includes a transformer, a digitizer, an activity detector, a decoder, a framer, a clock and data recovery circuit, a first driver circuit, and a second driver circuit, having an input connected to the second output of the clock and data recovery circuit, and having an output; at least one third channel, where each third channel includes a transformer, a digitizer, an activity detector, a decoder, a clock and data recovery circuit, a first driver circuit, and a second driver circuit; at least one fourth channel, where each fourth channel includes a transformer, a fanout circuit, a digitizer, an act