A complete series of hourly values of foF2 considered representative of geomagnetic quiet conditions is determined using the incomplete series of observed hourly values at Concepción (36.8º S; 73.0º W) in the 1 March 1958 - 1 July 1989 interval. This series takes into account known seasonal and solar activity level dependencies. Then a simple algorithm is proposed to calculate the missing hourly values of the original series, which takes into account the geomagnetic activity level for the corresponding hours, in terms of a weighted geomagnetic activity index. Since there is no way to assert the goodness of the proposed algorithm when there is no observed foF2 values, calculated and observed values are compared for a few days for which they do exist. Days considered representative of different seasons and levels of solar and geomagnetic activity are used. It is found that differences between calculated and observed values are not significant except for equinox and summer conditions at high geomagnetic activity level.
Critical frequency; F-region; Ionosphere
