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The Capacitor-fed Power Supply

The   capacitor-fed power supply is sometimes referred to as a TRANSFORMERLESS POWER SUPPLY. This article is going to shock you because it is going to tell you all the reasons why you should NOT design, produce or use a CAPACITOR-FED…
LED Tester

This. project is very simple. It is just a 4.5v supply with a LED and resistor in series. When the two probes touch they complete the circuit and the “test LED” (the red LED) will illuminate. When the probes are…
1 watt LED Lamp

This circuit is an extension of the 1-watt LED Driver project. It is a very clever circuit and will illuminate up to six 1-watt LEDs or 30 white LEDs to give an overall illumination of about 1 watt. The 1-watt…
1 watt LED Driver

This circuit will drive a 1 watt LED from 1 or 2 cells (commonly called “dry cells”). The circuit consists of only 4 components plus a LED and the secret to its operation is the transformer. It is operated in…

This circuit provides a visual 9 second delay using a 7 segment digital readout LED. When the switch is closed, the CD4010 up/down counter is preset to 9 and the 555 timer is disabled with the output held high. When…

This circuit provides a visual 9 second delay using 10 LEDs before closing a 12 volt relay. When the reset switch is closed, the 4017 decade counter will be reset to the 0 count which illuminates the LED driven from…

The two circuits below illustrate opening a relay contact a short time after the ignition or ligh switch is turned off. The capacitor is charged and the relay is closed when the voltage at the diode anode rises to +12…