Variation of the solar constant during 1983 and 1984

Measurements of the Nimbus-7/ERB and SMM/ACRIM radiometers indicated several dips in the total solar irradiance in 1983 and in the first part of 1984. The dips in 1983, which should have a real solar origin, were selected according to the peaks of the projected areas of the active sunspot groups above the 2 error limit of their data set. In the first part of 1984 the sunspot activity was strong and few irradiance dips with relatively large amplitudes were observed. In the second part of 1984 the sunspot activity disappeared and at that time the solar constant only fluctuated around its mean.