Eye diagrams are made for signals on each channel in a group. Outlying signals not exhibiting overlap for a sampling parameter common for all channels may be ignored and a warning given. Selected, normalized eye openings are used to discover optimum sampling parameters for each channel. Locations within each eye opening are ranked according to preference. Algorithms are used to select a single best value for a sampling parameter common to all the channels, and the corresponding best other sampling parameter is found for each channel. One algorithm disregards good choices for many channels to accommodate any remaining channel by using only a commonly agreed upon value (a jury system). Another algorithm gives weight to a choice according to the number of channels that agree on that choice (majority rule). A graphical user interface facilitates the selection, and emphasizes which sampling parameters are constrained to vary together.