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.
The integrated circuit used in this old configuration is not common today. In it we have the way...
In the figure we have a diagram of a thermostat using an NTC and an operational amplifier 741. The...
For those who work with reproduction or development of photographs or simply like to cook their egg...