The virtual height of the ionograms, manually and automatically scaled parameters have been calibrated in July 2025.
【Target Station and Period】
・Wakkanai/Sarobetsu（WK546）：Observation after May 13, 2016
・Kokubunji（TO536）：Observation after May 15, 2017
・Yamagawa（YG431）：Observation after January 1, 2017
・Okinawa/Oogimi（OK426）：Observation after Nobember 27, 2017
【Calibration Details】
・Virtual height of ionograms become 24km heigher than the original one.
・Manually and automatically scaled h'Es, h'E, h'F, h'F2 increase by several to 20km, depending on parameters.
・We have started 5-minute inverval operation on June 1, 2020.
・There may be irregular delays in updating data due to system maintenance or equipment failure.
・The service may be suspended when access is concentrated.