(Left) Sources observed at each station, as a function of observing time. OJ 287 is shown with red color, and the other calibrators are also shown with different colors: 3C 345, 1633+382, 0716+714, 0235+164, 3C 84, and NRAO 150. Among them, the 0716+714 is suitable to compare the station-based gain correction with the OJ 287, thanks to its station coverage. (Right, top) The (u, v)-coverage towards 0716+714 and its image are shown. Note that the SRT has not observed this source and the longest baseline length is limited up to ∼50 Mλ so the angular resolution (∼4.5 mas) is much poorer than for OJ 287. (Right, bottom) The multiplicative gain correction factors at each station, derived from OJ 287 (red) and 0716+714 (cyan). Different markers indicate each IF from 1 to 4 at each station.