This circuit was found in RCA documentation from the 1960s. The circuit uses components from that time and can measure speeds up to 10,000 rpm.
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...