This circuit is from an ancient American documentation. The transistors are of the time and the circuit uses a special sensor to detect the trigger point to produce spark plugs.
This circuit determines the frequency of a signal by beating with a known signal. The circuit was...
With the values of the components indicated, this timer controls intervals from a few seconds to a...
The purpose of this circuit is to automatically turn a water pump on and off. Sensor 1 is the...