Synthetic d.c. restoration of a.c. coupled signals

摘要

First and second signals are selected from a plurality of sequentially fed, a.c. coupled signals. A difference signal which is the difference between the first and second signal is generated. The times during which the first signal exceeds the second, and during which the second signal exceeds the first, are determined. The larger of these two times is selected and an average of the difference signal over this larger time is generated. The average is added to the second signal. Means for implementing these steps, including an all analog embodiment are disclosed.