Ultrasonic Dog Whistle

Variable Power Supply LM317

A truly timeless circuit. LM317 is a versatile and highly efficient 1.2-37V voltage regulator that can provide up to 1.5A of current with a ... Baca selengkapnya »

Simple Radio Wave Alarm

This simple circuit is sure to have the police beating a path to your door- however, it has the added advantage of alerting you to their pre... Baca selengkapnya »

LM317-Variable DC Power Supply

LM317-Variable DC Power Supply Circuit diagram : This power supply is based on the LM317 Variable Regulator. The input of the regulator n... Baca selengkapnya »

Regulated 12 Volt Power Supply

A basic regulated 12 Volt power supply. Regulated 12 Volt Power Supply Circuit diagram : Note : This circuit above uses a 13 volt zener ... Baca selengkapnya »

Pulse Charger for Reviving Tired Lead Acid Batteries

If you own a motorcycle, a motor home, a caravan, a lawn mover, a day cruiser or maybe a vintage car you must at some point had to write off... Baca selengkapnya »

DIY Tremolo Effect

This tremolo effect circuit uses the XR2206 and the TCA730 IC which is designed as an electronic balance and volume regulator with frequency... Baca selengkapnya »

Fox Hunt Transmitter

This 2 meter 144 MHz fox hunt transmitter is used in amateur competitions where a hidden transmitter is to be “hunted” using mostly home bre... Baca selengkapnya »

Polyphonic DoorBell

Here is an AC triggered Multitone, polyphonic doorbell. It gives eight melodious tunes for 2 minutes. On each press it will give a new tone... Baca selengkapnya »

Photodiode Alarm

This Photodiode based Alarm can be used to give a warning alarm when someone passes through a protected area. The circuit is kept standby th... Baca selengkapnya »

5V Power Supply Using LTM8021

This 5v power supply circuit is designed using the LTM8021 and will provide a maximum current up to 500mA. Almost all required parts are i... Baca selengkapnya »

Solar Power Supply

This circuit delivers either 4.8 or 7.2 V regulated at 15 mA with a 3-V input from a bank of photocells. Rl should be 453 kQ for a 7.2-V ou... Baca selengkapnya »

30V Variable Power Supply Using LM317

This 30v variable power supply circuit is based on LM317  voltage regulator circuit . This LM317 30v variable power supply circuit can del... Baca selengkapnya »

Variable Power Supply Using LM723

Using LM723 regulator can be designed a very simple variable power supply circuit which can provide a maximum current up to 2A and a varia... Baca selengkapnya »

Dual Regulated Power Supply

In this circuit, the 7815 regulatates the positive supply, and the 7915 regulates the negative supply. The transformer should have a primary... Baca selengkapnya »

Portable CD Player Adapter For Car

Whenever I'm in the car listening to my favourite CD, it always happens; my batteries go dead. To solve that problem, I built this extre... Baca selengkapnya »

Batteries Charger & PSU - Ideal for Digital Cameras

This circuit was created for digital cameras. It's known the digital cameras have considerable power consumption. For example my camera ... Baca selengkapnya »

Telephone Tapping Indicator

This simple circuit can indicate a misuse or tapping of Telephone line through a loud alarm. The circuit is too simple and can be easily ass... Baca selengkapnya »

Automatic Load Sensing Power Switch

This circuit will automatically switch on several mains-powered "slave" loads when a "master" load is turned on. For exa... Baca selengkapnya »

7 Watt Audio Amplifier Using TDA2003

Amplifier Circuits Diagram Schematic diagram of a simple 7 watt audio amplifier using TDA2003 Amplifier IC. This is a good IC with man... Baca selengkapnya »

Single Supply Function Generator

The circuit has both square-wave and triangle-wave output. The left section is similar in function to a comparator circuit that uses positiv... Baca selengkapnya »

12V Battery Charger

This circuit is a high-performance charger for gelled-electrolyte lead-acid batteries. This charger quickly recharges the battery and shuts ... Baca selengkapnya »

Simple UPS Power Supply

This circuit is a simple form of the commercial UPS, the circuit provides a constant regulated 5 Volt output and an unregulated 12 Volt supp... Baca selengkapnya »

Fixed Voltage Power Supply

The fixed voltage power supply is useful in applications where an adjustable output is not required. This supply is simple, but very flexab... Baca selengkapnya »

Solar Charger for Lead-Acid Batteries

This circuit is still under development, but works well as shown. This circuit is intended for charging lead-acid batteries with a solar pa... Baca selengkapnya »

Multi-Color LED

How many different conditions do you reckon may be signalled with just one LED? Two, maybe three? Using this simple circuit, a lot more! Adm... Baca selengkapnya »

Simple 40 Watt Inverter

This is the schematic of a simple 40W , 12 volts to 220 Volts inverter.You don’t believe, this is simple and cheap and working for me for la... Baca selengkapnya »

Piezo-Powered Lamp Circuit Schematics

Energy is becoming ever more expensive, and some fresh ideas are needed. There are already human-powered devices on the market, most of whic... Baca selengkapnya »

Simple Low Cost 100W Inverter

Here is the circuit diagram of a simple 100 watt inverter using IC CD4047 and MOSFET IRF540. The circuit is simple low cost and can be even ... Baca selengkapnya »

220 Volts Flashing Lamps

Especially designed for Christmas tree lamps Replaces old thermally-activated switches This circuit is intended as a reliable replacement ... Baca selengkapnya »

VU Meter 5 with UAA180

This circuit of measurement of level uses the UAA180 of SIEMENS and a circuit of rectification of precision, round the IC2B. The calibration... Baca selengkapnya »

IR Beam Breaker Schematics

This is an Infrared beam breaking alarm ideal to use in entry or passages.It is based on the working of the popular IR sensor Module TSOP 17... Baca selengkapnya »

Simple Low Power Car Stereo Amplifier

A simple low power car stereo amplifier circuit based on TDA 2003 is shown here. The circuit uses cheap, readily available components and it... Baca selengkapnya »

Small Power Amplifier 8W / 8Ω with TDA 2030

Although the TDA2030 can deliver 20 watts of output power, I deliberately reduced the output power to about 8 watts to supply 10 watt speake... Baca selengkapnya »

Motional Feed Back Amplifier

This concept has appeared long back in Practical Electronics a UK based Magazine. Based on this concept I designed this circuit during 1981 ... Baca selengkapnya »

Simple Nicad Battery Charger

This simple charger uses a single transistor as a constant current source. The voltage across the pair of 1N4148 diodes biases the base of t... Baca selengkapnya »

High Current Power Supply

Since my page was first posted, I have received a number of emails asking about a high current power supply. I looked around, but couldn'... Baca selengkapnya »

Running Message Display Schematics Circuit

Light emitting diodes are advantageous due to their smaller size, low current consumption and catchy colours they emit. Here is a running me... Baca selengkapnya »

Dual Mode Battery Charger Circuit

There are two main types of battery charger – constant voltage and constant current. Both have their advantages and disavantages. For consta... Baca selengkapnya »

Simple FM Microbug

Although the idea has been around for a good while already, it’s still cute: a tiny circuit that you can hide just about anywhere for all so... Baca selengkapnya »

60W Inverter using transistors

Here is the circuit diagram of a fully transistorized inverter that can drive up to 60W loads. Transistors Q1 and Q2 forms a 50Hz astable mu... Baca selengkapnya »

Simple LED Torch

A common problem with small torches is the short life-span both of the batteries and the bulb. The average incandescent torch, for instance,... Baca selengkapnya »