This circuit was found in a Popular Electronics from the 90s. The counter circuit is not common today. The circuit can be programmed for hourly intervals, according to the values of R4 and C2.
This circuit appears elsewhere on the site. The circuit shown is from an American 1980s...
This circuit changes an audio signal to get better reproduction. It is important when editing...
The circuit shown is a Step-Down converter that can provide a 5 A output with 4 to 18 V inputs. The...