Integrated spectrum (Q1b) for all beams in all observations for 55 Cnc (panels a and b), υ And (panels c and d), and τ Boo (panels e and f). Large scale features are seen for all dates, however, they change between observations. Panels c–f: ripple pattern that is likely due to an instrumental effect (e.g., imperfect phasing). There are no large-scale differences seen between thetwo OFF beams (bottom plots in panels a, c, and e) for any date. In every individual observation, the two OFF-beams and ON-beam (expect L570725) are equivalent with each other within the pure Gaussian noise error bars (). Dynamic spectrum differences of all OFF beams in every τ Boo observation can be found in Fig. I.1. The τ Boo ON-beam signal in observation L570725 (orange curve in panel f) is the only large-scale difference between the ON and OFF beams that is seen (bottom plot in all panels). The 20–30 MHz features in many of the τ Boo b dates are the same order of magnitude as the ON-beam signal in observation L570725 (panel e). The dynamic spectrum of the ON-beam in observation L570725 subtracted by the OFF beams in the other τ Boo observationscan be found in Fig. I.1.