Schematic Diagrams

Useful schematic and wiring diagrams. ✔ ✔ Enjoy electronic circuits, let your idea comes to hardware


Quick Counter For Young Children

This circuit is a toy to encourage young children to count. Power is turned on by switch S1, then S2 is closed. This makes nine LEDs flash slowly. S2 is then opened and the LEDs go out. Pressing pushbutton PB1 turns on a random number of LEDs – briefly – during which time they are […]


High Voltage Generator for Geiger Tubes

High Voltage Generator for Geiger Tubes These circuits generate high voltages and can cause dangerous shocks! Do not build these devices unless you are experienced and qualified to work on high voltage devices. The following two circuits are an improvement over the older circuits below. The circuits are shown generating 500 volts but they may […]

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Geiger Counter Power Supply

Techlib reader Dave Mouat modified the circuit as shown below:     In the diagram I’ve put the transistor numbers as the ones I’ve used, although you can use standard 2n3904’s etc in these positions without problems as they’re similar spec. The transformer used is a normal audio output transformer, such as an LT700, and […]

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Analogue Pulse Counter

Introduction Although this is a fully functional circuit, it contains several interesting bits: in detail, there’s perhaps nothing hugely original about it, but in ins overall inception is is an imaginative solution to the problems that were posed, It was designed for an application in a welding machine: there are lots of bits of machinery […]

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MM5452 Liquid Crystal Display LCD Drivers Circuit Diagram and Datasheet

The MM5452 is a monolithic integrated circuit utilizing CMOS metal gate, low threshold enhancement mode devices which can drive up to 32 segments of LCD and can be paralleled to increase this number. This devices is usually applicable for microprocessor display, industrial control indicator, digital clock, thermometer, counter, voltmeter, instrumentation readouts and remote displays. The […]

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Digital 7 Segment Pulse Counter

A pulse counter can be built by using 7490 decode counter and 7557A. This circuit can count from zero to 9. Pins 3 and 2 of all 7490′s must be connected together. Here is the schematic diagram of the circuit: A push button is used as reset. The input of this circuit is a pulse […]


Performance and Characteristics of CT2 Counter/Timer Module

The CT2 counter/timer module device perform convertion of a PC into a high performance pulse counting instrument. It is used specifically to count all TTL photon counting packages and TTL amplifier-discriminators Electron Tubes. This module can operate the following operations: continuous readings, fixed number of readings, continuous readings – trigger high, and fixed number of […]

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