Random circuits

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Mains Operated LED Circuit Schematic

Here is a simple and powerful LED circuit that can be operated directly from the AC 100 volt to AC 230 Volts mains supply. The circuit can be used as mains power locator or night lamp etc.. The resistor R1,R2 and capacitor C1 provides necessary current limiting. The circuit is sufficiently immune against voltage spikes and surges.... [read more]

Muscular Bio-Stimulator

This is a small, portable set, designed for those aiming at look improvement. The Bio-Stimulator provides muscles' stimulation and invigoration but, mainly, it's an aid in removing cellulitis.... [read more]

220 Volts Flashing Lamps

This circuit is intended as a reliable replacement to thermally-activated switches used for Christmas tree lamp-flashing.... [read more]

Power amplifier 60W/8Ω

This circuit was designed and manufactured the '80's. From then it works without problem. It does not present any particular constructional problem, beyond known: the attention in the provided force of power supply - choice suitable heatsink and good matching of drivers transistor.... [read more]

Simple Lie Detector

Here's a simple lie detector that can be built in a few minutes, but can be incredibly useful when you want to know if someone is really telling you the truth. It is not as sophisticated as the ones the professionals use, but it works. It works by measuring skin resistance, which goes down when you lie.... [read more]

A Low Cost Hearing Aid

This low-cost, general-purpose electronic hearing aid works off 3V DC (2x1.5V battery). The circuit can be easily assembled on a veroboard. For easy assembling and maintenance, use an 8-pin DIP IC socket for TDA2822M.... [read more]