A system of synchronized radio telescopes is utilized to search for hypothetical wide bandwidth interstellar communication signals. Transmitted signals are hypothesized to have characteristics that enable high channel capacity and minimally low energy per information bit, while containing energy-efficient signal elements that are readily discoverable, distinct from random noise. A hypothesized transmitter signal is described. Signal reception and discovery processes are detailed. Observations using individual and multiple synchronized radio telescopes, during 2017 - 2021, are described. Conclusions and further work are suggested.