spase://ASWS/NumericalData/Ionogram/Auk_Ionogram

An Ionogram is an image of frequency versus time delay (virtual height) of HF echoes from the ionosphere recorded by an ionosonde. An ionosonde is a swept frequency HF pulsed radar used to monitor the ionosphere. SWS WDC has archived ionogram data from 26 stations, 12 of them still active at present. An IPS 4D ionosonde had been sounding between 15/12/1992 and 31/03/1998 at Auckland. The 4D vertical sounding ionosondes normally sweep in frequency from about 1.0 to 21.5 MHz. Frequency step resolution for the 4D is 5 kHz, with up to 4095 steps available. The step interval is variable, becoming more coarse at higher frequencies as ionograms are generally displayed on a logarithmic scale. Every five minutes, a Ionogram data file is recorded. The raw ionogram file is recorded in a DVD monthly, which will be posted to Sydney SWS head office every month for scaling and further analysis. SWS WDC archives all raw ionogram files and cleaned ionogram files. The Auckland digital clean ionogram data is available since 01/01/1998 to 01/02/1998. The Auckland scaled hourly ionospheric data include parameters of foF2, foF1, FoE, foEs, fbEs, fmin, fxl, f'scaling F/s, M(3000)F2, h'F2, h'F, h'E, h'Es, h'Scaling R/S and Type Es. They are available since 01/01/1970 to 31/12/1978. The Auckland median data of foF2 and M(3000)F2 are available since 01/1967 to 12/1978.