Found in a 1968 Novel Electronics Circuit, this circuit compares two light intensities using common LDRs as sensors. Transistors can be modern PNP equivalents.
This small automotive NiCad battery charger uses only passive components and has the number of...
This different circuit uses a relay as an oscillator, whose frequency is determined by C1, and to...
In this circuit we show how to modulate the pulses produced by a 555 in frequency. The circuit can be...