Found in a 90’s Popular Electronics, this circuit uses two CMOS inverters to generate a signal of a few hundred hertz determined by C1 and the R3 setting.
The figure shows how to implement an OR function with two inputs, using a relay. The relay...
The integrated circuit used in this 1987 project is not very common these days. However, if found...
Found in American documentation from the 1980s, this circuit has a diode feedback. At the exit we...