High impedance window comparator (CB6091E)

General Electric suggests this circuit in a 1980s documentation. The operational of the time is FET-type input. Modern equivalents may be used.

| Clique na imagem para ampliar |

Heterodyne Frequency Meter (CB22320E)
This circuit determines the frequency of a signal by beating with a known signal. The circuit was...
Variable Timer 555 (CB15097E)
With the values of the components indicated, this timer controls intervals from a few seconds to a...
Water Pump Automatic Control (CB18101E)
The purpose of this circuit is to automatically turn a water pump on and off. Sensor 1 is the...