In the present work, we discuss two phenomena of 25 feb. 1969, measured at 408 MHz with the radiotelescope of the Observatorio Nacional de Física Cósmica de San Miguel. Both events are of spectral type IV and they originate on the same center of activity. We analyze the radio events at various frequencies and conclude that they are homologous. Finally, we suggest and discuss some ideas about certain characteristics of invariance of the active region.