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Transistor / Diode / IC (DIP) Outlines

Transistor / Diode / IC (DIP) Outlines... [read more]

Symmetrical Preamplifier Class A

This is a symmetrical amplification unit circuit, more composed, modified by a construction which was proposed some years ago by Lisley Hood. The most important reason is to get the right transistor FET at differential amplifier at input. In spite of all this it is a circuit which provides, current mirror stage of both sides, with the result of lessening the overall negative feedback.... [read more]

High-intensity LED Warning Flasher

This circuit was designed as a warning flasher to alert road users to dangerous situations in the dark. Alternatively, it can act as a bicycle light (subject to traffic regulations and legislation). White LEDs only are recommended if the circuit is used as a bicycle front light (i.e. for road illumination) and red LEDs only when used as a tail light. During the day, the two 1.6-V solar cells charge the two AA batteries. In darkness, the solar cell voltage disappears and the batteries automatically power the circuit. The flash frequency is about one per second and the LED on-time is about 330 ms.... [read more]

Digital Roulette with Display

This circuit is a small digital “roulette''. It is constituted by oscillator IC1, the counter IC2, the transistors Q1-7 that drive the display common cathode DSP1. The supply basically becomes from a battery 9V, but can become also from one power supply.... [read more]

Electronic Canary

Feeling chirpy? Attract new friends with this modified hartley oscillator. You could also use it as a replacement doorbell.... [read more]

Adjustable 1.3-22V Regulated Power Supply

Want a regulated voltage that can be adjusted to suit your application? This Adjustable Power Supply is small, easy to build and can be adapted to produce a fully regulated voltage ranging from 1.3V to 22V at currents up to 1A.... [read more]