Blog Feed: Many circuit project electronics

The good electronics how?

Published on 2012-05-25 03:49:07

We use electronic devices. But most of us do not really know what goes on. Once inside it. But the understand some basics about electricity and electronics. Can be worthwhile for three reasons: 1. Learning how the technology works, you will become can control world, instead of being controlled by it. 2. Learning about electronics [...] > read more

Band rejection filter using TL071

Published on 2012-05-15 14:47:01

The band rejection filter circuit is not wide filter that can denial the frequency up to 60dB by we used the TL071 single chip op-amp it is very low distortion and work good at output to maximum to 100kHz or the range 1Hz to 20kHz In the circuit we defined three resistors R1,R2,R3 are like [...] > read more

Precision half wave rectifier using op-amp

Published on 2012-05-09 23:19:38

This circuit provides for right half wave rectification of the input signal. The op-amp IC no-NE5535 is Dual High Slew Rate Op-Amp, it is used for main of this circuit. The input signal have two-phase supply are Fist, positive signals is the gain is 0; And second, negative signals is the gain is – 1. [...] > read more

50 ohm driver circuit

Published on 2012-04-30 01:52:51

When you are connected to buffer a tester to outside tool, we should have an booster with enough bandwidth and power disposition ability. This circuit is a very simple for unity gain buffer; it is only two pairs of emitter followers. The base emitter voltages of Q1 and Q2 cancel out, and so do those [...] > read more

Visual zero beat indicator

Published on 2012-04-29 03:48:04

This circuit is suitable for an indicator to audio signal lower than 3Vp-p. In the circuit, we use a very small parts with only two of the LED display and built-up resistor for current depression. Light-emitting diodes(LED) connected with reverse polarity provide a visual indication of zero-beat frequency. Each Led is on for only half [...] > read more

Purpose power supply using LM723

Published on 2012-04-16 10:27:10

General Purpose Power Supply by L146 or IC 723 This power supply is designed for general purpose use. Advantages of the circuit are first the voltage can be adjusted from 0V to greater and second it does not require a double sided secondary winding transformer. For high voltage outputs you can use L146 or alternatively [...] > read more

High Q notch filter

Published on 2012-04-10 20:59:07

In the circuit shown, Twin-T network connections with LM102 in form of High Q notch filter. Usually, the junction of R3 and C3 to ground, is bootstrapped to the output of the follower. Because it has a very low impedance,neither the depth nor the frequency of the notch change. However, Q increases in proportion to [...] > read more

Precision Peak voltage detector with a long memory time.

Published on 2012-04-04 00:18:49

If you want to check the peak voltage of the signal to change at any time. Measuring with a multimeter will not do it. We recommend this circuit. It may help you. We use this circuit The op-amp IC number CA3140 is the main equipment, acts as a voltage sensor that is accurate. So It [...] > read more

Background music decoder

Published on 2012-03-31 05:35:53

This is a background music (SCA) decoder circuit from the input demodulated (multiplex) FM signal. We use NE565 (Phase Locked Loop IC) to be base of this circuit, for easy and cheap. A resistive voltage divider is used to set a bias for the input (pins 2 and 3). The input passes through a two-stage [...] > read more

Crystal oscillator using TTL

Published on 2012-03-30 05:25:27

This are simple and cheap crystal oscillator circuit, that we use a few parts comprises a TTL digital number SN7404 (Package contains six inverters), four resistors and a crystal. The tree inverters gate are biased into their linear regions by R1 to R4, and the crystal provides the feedback. Oscillation can only occur at the [...] > read more

Precision current sink circuit

Published on 2012-03-29 00:51:33

This is a current sink circuit that uses a transistor, Jfet and LM101 IC op-amp, so there are high precision. The 2N5457 Jfet and PN2222 bipolar have normally high output impedance. The R1 is used as a current sensing resistor, for provide feedback to the LM101 op-amp that it supply a large amount of loop [...] > read more

5V to isolated 5V at 20mA converter by MAX635

Published on 2012-03-28 08:13:55

When we need a constant voltage 5V at the current about 20mA, by there are power supply source voltage about 4V to 6V. In this circuit, We use the MAX635 IC number is the main equipment, that acts as Preset/Adjustable Output CMOS Inverting Switching Regulators. At pin A, a negative output dc-dc converter generates a [...] > read more

12V Battery charger using UJT

Published on 2012-03-21 11:49:09

This is an automatic 12V battery charger circuit, they uses the power SCR and UJT are main parts. And they will not work except the battery 12V to be charged with right polarity, so prevent errors as well. The battery voltage controls the charger and when the battery is fully charged, the charger will not [...] > read more

Dual limit comparator with LM709

Published on 2012-03-07 01:25:40

This voltage comparator circuit gives a positive output when the input voltage is a positive or negative more than 8.5V. But in between that the output is negative voltage. The positive limit point is defined by the ratio of R1, R2, and the negative point by R1, R3. The forward voltage drop across the diodes [...] > read more

Musical chime generator with ua741 oscillator

Published on 2012-03-03 12:13:17

This is a musical generator that uses bandpass filter circuit with ua741 op-amp as act converts a sound signal in multiple feedback patterns. When connected the voltage input from a rhythm generator with a short pulse , makes it ring in natural resonance frequency. As the output oscillations vanish suddenly and resemble percussion or strum [...] > read more

Single transistor phase shifter

Published on 2012-03-02 05:48:57

This is a basic NPN transistor circuit which it provides a simple mean of obtaining phase shifts between zero and 170 degree. The BC108 transistor works as a phase splitter, the output at point A being 180 degree without phase from the input. Then Point B is in phase with the input phase. Adjusting R1 [...] > read more

Power line frequency meter

Published on 2012-03-01 04:22:06

This is the meter show the frequency of a power generator, which it has voltage 110V-240V at 10-100HZ. The output sine waves are converted to square waves by the 100k 2 watt resistor and the 6.8V 1watt (1N3829A) zener diode. Then the square wave is transformed by the 0.22uF capacitor and the current is averaged [...] > read more

Wien bridge oscillator with FET

Published on 2012-02-27 10:32:20

Wien bridge oscillator is sine wave oscillator. It can generate a big of frequencies. The oscillator has based on a bridge circuit, which compose four resistors and two capacitors. The oscillator can also be viewed as a positive gain amplifier combined with a band pass filter that provides positive feedback. The field effect transistor (FET) [...] > read more

Easy in-line rf wattmeter circuit

Published on 2012-02-09 10:29:52

This is a little ideas of Easy In-line RF wattmeter circuit, it is insensitive to frequency, so calibration will be correct better than a wide frequency spectrum. For example the whole amateur HF spectrum; If the values of L2, the voltage divider at capacitors C1 and C2, and the resistances of R1 and R2 are [...] > read more

The Safe constant current source.

Published on 2012-02-07 01:32:02

Figure the top is a Safe constant-current source circuit, how it works? A cmos op-amp (number ICL 7611) controls the input current through a P-channel Hexfet power transistor (No. IRF 9520), then to keep up a constant voltage across the R1. As they are connected in a serial form, so use the together current by: [...] > read more

The universal battery charger using Lm317

Published on 2012-02-04 04:51:09

Here comes very simple idea is the universal battery charger circuit. When, an input power is applied to the circuit. The SCR1 (Silicon controlled rectifier) turn off, then not has a bias current path to ground. The LM317 acts as a current regulator, It is connected to the battery thought a one way diode D1, [...] > read more

simple nonlinear low pass filter

Published on 2012-01-23 00:54:06

This simple circuit is nonlinear passive on low pass frequency filter. It ‘s small size and easy to made for do not used the external power supply, but refuse a lot of noise ripples and need to a input voltage is stable. The circuit works best, when the signal level is importantly higher than the [...] > read more

Light meter by LM334

Published on 2012-01-16 07:58:15

The light meter is a tool, measure the quantity of light, widely used to a photography, To decide the correctness of the exposure. Sometimes, we are use with other works, such as my son likes to use in science experiments, which do not need to have high quality. This simple light meter in figure 1 [...] > read more

IRF540 MOSFET N-CH 100V 33A TO-220AB

Published on 2011-12-25 07:54:55

Specifically designed for Automotive applications, this HEXFET® Power MOSFET utilizes the latest processing techniques to achieve extremely low on-resistance per silicon area. • VDSS = 100V • RDS(on) = 26.5mOhm • ID = 36A. Read more > read more

Alpha Potentiometer 25K Linear

Published on 2011-12-25 07:51:07

Guitar Amp Potentiometer. Audio/Log pots are typically used for volume control, and Linear pots are typically used for effects. 25KL / 25K Linear / 25KB / 25,000 ohms. Fits 3/8″ Hole. 1/4″ Solid Shaft. 24mm Body, Solder Lugs, 1/2 Watt Rated, 300° Rotation, 250VDC Rated, Carbon Composition. Comes With Hex Nut and x2 Washers Read [...] > read more

microtivity 5mm Assorted Clear LED

Published on 2011-12-25 07:44:49

Contains 10 Clear Reds, 10 Clear Yellows, 10 Clear Greens, 10 Clear Blues, 10 Clear Whites and 10 Clear Pinks. These light-emitting diodes work well for a wide variety of applications including Arduino projects. Comes with some resistors for connection. Forward Voltages are Clear Red and Clear Yellow 1.9-2.0V, Clear Green: 2.9-3.1V, Clear Blue, Clear [...] > read more

Chocolate style keyboard

Published on 2011-11-28 23:03:12

Now I have a problem keyboard of my laptop,very hot. My friend Tom said, I should to change was a external keyboard,wireless stye is so well. I loved a laptop keyboard,it is chocolate style softly and slim. But found difficultly and expensive,too. I saw on www.amazon.com,the one keyboard was very interesting,comfortably compact,tight workspace,saving size, etc. [...] > read more

The resistors kit 86Value 860 Pcs.

Published on 2011-11-14 00:22:12

Read more When we made the electronic projects. The resistors was important component because we use more value and too much code. We must had a lot of resistors in store. But where to be buy they. Follow to I search in internet,founded The Joe Knows Electronics 86 Value 860 Pc. Resistor Kit ,good produce [...] > read more

Mini roulette system

Published on 2011-07-05 10:56:36

A mini roulette circuit, When the switch S1 the output at pin 1 of the IC1a the voltage is “high”,The oscillator circuit output IC2b, IC2c work.Clock pulse generator fed to IC3, a voltage “high” output to the output pins 3, 11 > read more

Digital 9500 Finger Pulse Oximeter

Published on 2011-07-03 23:20:52

The Original All-in-One Digital Fingertip Pulse OximeterTM Pulse Oximetry at Your Fingertips, Anywhere, Anytime NONIN revolutionized pulse oximetry with the Onyx. Hundreds of thousands of people trust Onyx, the first self-contained digital fingertip > read more

Synthesized FM Stereo Transmitter Kit

Published on 2011-07-03 23:07:15

Need professional quality features but can’t justify the cost of a commercial FM exciter? The FM25B is the answer! A cut above the rest, the FM25B features a PIC microprocessor for easy frequency programming without the need for look-up tables > read more

Rotary electronic switch

Published on 2011-07-03 19:25:13

Rotary switches electronic circuits, using a single switch choose a function of external control circuit has 9 positions.Work was, when the switch S1, the output signal from pin 2 of IC1, a “high” at all, and the pulse signal to IC2, the > read more

Factory Assembled AR2L

Published on 2011-07-03 00:31:34

Because many small airports do not have any control personnel on duty, especially at night, it is necessary to either have the runway lights activated at all times to allow planes to land or have some method of allowing a pilot to turn on the lightin > read more

Audio/RF DDS Signal Generator

Published on 2011-07-03 00:07:35

Announcing our NEW SG560 Signal Generator! We increased the frequency range all the way up to 5MHz and all the way down to 0Hz (yes, we mean zero…or DC!) continuously in 0.1Hz steps across the entire range! Next we increased the output level to > read more

Flashing brake lights

Published on 2011-07-02 20:04:10

This circuit will allow the brake light was flashing.The default behavior. When the power supply to the circuit, Or tap the brake it.The IC timer IC2 drive current to transistor Q2 and producing oscillator output, pulse signal output at pin 3 to inpu > read more

Davis Wireless Weather Envoy

Published on 2011-07-02 01:42:08

Wireless Weather Envoy™Receive data from a wireless Vantage Pro2 integrated sensor suite or wireless Temperature Temperature/Humidity or Leaf Wetness & Soil Moisture/Temperature stations and post it to your computer without a console! When use > read more

2ch Recorder Isolated 12/24VDC Power Input And USB

Published on 2011-07-02 01:21:42

The DataChart 1250 is a powerful, compact digital recorder with intuitive operation, flexible input configuration and large memory capability. Combining small package size with extreme flexibility make the DataChart 1250 a powerful, yet economical, d > read more

Buy HandHeld Spectrum Analyzer

Published on 2011-06-28 21:38:05

Built-in calibrated measurement microphone 1/3 octave real-time analyzer 31-band EQ setting value display (boost/cut) RT60 reverb time measurement Phase checker Noise generator with pink noise, 1kHz and polarity test signal, balanced output Memory an > read more

Delay switch turn on the monitor

Published on 2011-06-28 07:21:26

This is a time delay switch on the monitor. The contacts of the relay acts as a switch.The contacts of the relay, acting as a switch.When entering into the 220volt mains. Circuit delay for a while. To reduce current surges, gradually flowing into it, > read more

Bench Dog Tools Cast Iron Router Table Extension

Published on 2011-06-26 19:39:48

Expand your table saw’s versatility by adding this industrial grade router table in place of the extension wing. Perfect for shops where space is tight, ProMAX includes a cast-iron top, Bench Dog’s 28″ ProFence, a miter gauge track > read more

Hayward Goldline Controls Aqua Logic Main PCB Board

Published on 2011-06-26 19:16:48

GLX-PCB-MAIN AQL-PCB-MAIN Main PCB, AquaLogic All Versions All Date Codes Goldline Controls, Inc., began as Independent Energy, Inc., a company founded in 1975 by two engineers who graduated from Brown University. Independent Energy initially focused > read more

Wide band high frequency amplifier

Published on 2011-06-25 06:10:03

High-frequency amplifier circuit,Wide frequency band between 75-150 MHz,Using transistors, a PNP amplifier.To enhance the signal strength.Before the receiver of the phone. Or FM radio or amateur radio. If high-frequency signals, in particular, its VH > read more

Buy Hybrid headphone amplifier

Published on 2011-06-25 02:08:36

The Little Country III paints a accurate musical reproduction regardless of the source. It features a rich, beautifully detailed sound from top to bottom and a superb soundstage. You’ll find yourself lost in the music – almost hypnotic li > read more

RF EMF Strength Meter

Published on 2011-06-25 02:02:09

This RF EMF Strength Meter monitors high frequency radiation in the 50MHz to 3.5GHz range. Ideal for mobile phones, cell phones, base stations, locating RF hotspots, wireless network (Wi-Fi) RF detection, RF”Electrosmog” detection, and mi > read more

PIR. motion sensor alarm circuit

Published on 2011-06-24 00:40:06

A motion detection alarm circuit using a PIR.SENSOR motion detection, if the move is a positive light from the PIR sensor, triggered by a delay circuit, Q1 and relay it to work and hold for about 20 seconds. to apply to the siren to signal a warning > read more

Zen Toolworks CNC Carving Machine DIY Kit

Published on 2011-06-24 00:03:23

This is just the CNC machine with motors. You will need a 3 Axis Stepper Motor Driver to manage each motor, a spindle/cutter(a Dremel would work) and a DC power supply for the driver. You will also need a computer with a standard printer port and CNC > read more

QM1000 Automatic Pick and Place Stand-Alone Machine

Published on 2011-06-23 23:52:41

Patent-pending technology applied in automatic picking up. 2000 estimated pph(parts per hour). Placement of 0402 standard (upgrade for smaller parts). Computer vision automatic centering system for IC’s (SOP, QFP, BGA) and better placement of s > read more

Xytronic 426DLX Fume Extractor

Published on 2011-06-23 23:05:44

The Xytronic 426DLX incorporates a built in high efficiency, low noise, brushless mini fan. Easy to replace activated carbon filter effectively absorbs noxious flux and lead fumes. Quickly removes smoke and fumes….. Read more > read more

Small stereo amplifier for computer with TDA7025

Published on 2011-06-23 05:30:41

Small stereo amplifier,low power, less devices, IC TDA7025 is the main equipment. Operation of the circuit, the signal split into left and right through the capacitor coupling of C1, C2 is a variable resistor VR1 adjusts the strength of the input sig > read more

BK Precision DC Electronic Load Programmable

Published on 2011-06-22 22:59:48

Affordable and full-featured with a high degree of accuracy and great display resolution. Ideal for DC power supply and DC-DC converter testing and calibration. Fully programmable via the RS-232 or optional USB interface, making it a great companion > read more

DC Power Supply Regulated Digital Display 0-60 volts 0-12 amps

Published on 2011-06-22 22:30:26

These CE certified Regulated DC power supply units comply with Power Supply Harmonics Current Regulations IEC1000-3-2, and a power factor of 95% (typical) is cleared. These models feature high reliability and various types of protection, and can be u > read more

Measure the distance by bicycle

Published on 2011-06-21 06:16:14

Operation of the circuit. Wreath switch S1 to detect the magnetic field. By S1 on the circuit.When a magnetic force drew near.When the magnetic field out away.It works in conjunction with resistors R1, R2 and capacitor C1.Pulse generator signal to IC > read more

Mini switches controlled by light

Published on 2011-06-20 07:23:10

Mini switch control circuits with light, by used the photo transistor is a light sensor, and Schmitt Trigger output drive current, Out a load or an external circuit,can supply up to 25 milliamps. This circuit uses less equipment. Can be used for smal > read more

Door buzzer sound with CD4001 CD4060

Published on 2011-06-18 09:07:39

The Door buzzer sound circuit was two-tone sound. With the switch S1. working of circuit,The IC1 is a frequency dividing circuit, and generator a sound frequency came out.by the C1, R1 are the frequency generator. This audio signal from pin 7 and pin > read more

over load protection for a transformer

Published on 2011-06-17 06:23:33

The working principle of the circuit. Start step, dc voltage power from the secondary coil of the transformer will be charged to C1. through D1.When the switch S1 to the circuit, current flows through relay contact at the NC,And flowing through the l > read more

DC motor controller diagram with SCR and cmos ic

Published on 2011-06-16 08:08:36

This is speed controller circuit of 12Volt DC motor.You can adjust the speed of rotation of the spindle motor from 5-60 cycles per minute. The work of circuit, The IC1 is nand gate ic type,It accepts the voltage from the bridge diode BD1. But there i > read more

Internal Resistance Tester For Batteries

Published on 2011-06-09 01:46:22

This circuit is designed to check the condition of lead-acid and gel cell batteries with capacities greater than 20Ah. It switches a load of about 18A at a rate close to 50Hz so that the internal resistance of the battery can be measured using a digi > read more

Doorbell for the Deaf

Published on 2011-06-07 06:18:14

This circuit provides a delayed visual indication when a door bell switch is pressed. In addition, a DPDT switch can be moved from within the house which will light a lamp in the door bell switch. The lamp can illuminate the words “Please Wait& > read more

Magic Wand Conjuring Trick

Published on 2011-06-07 06:13:05

The simple conjuring trick in Figure 1 is intended to provide some enjoyment for the beginner in electronics or conjuring, and should take only an hour or two to build. The trick works as follows: a wand (with a magnet mounted in one end) must pass i > read more

First time electronic learning with Snap Circuits SC-300

Published on 2011-06-06 05:59:59

Now my son, age 5 years.I want to find a good event for him in free time. Future he would be happy to create electronic projects. So I find information about Beginner electronic learning. On www.amazon.com site There are many interesting machines. Th > read more

Getting Started in Electronics

Published on 2011-06-05 22:22:16

This is a complete electronics course in 128 pages! Author Forrest Mims teaches you the basics, takes you on a tour of analog and digital components, explains how they work, and shows you how they are combines for various applications. Includes circu > read more

Light-Controlled Pond Pump

Published on 2011-06-05 00:22:03

This circuit was constructed to control the pump in a garden pond, so that it automatically turns on at dawn and off again at dusk. Not only does this mean that we don’t have to get cold and wet when turning the pump on or off manually but it’s a > read more

SE Digital battery tester 12V

Published on 2011-06-03 08:46:58

Easy-to-use, compact and accurate – pays for itself by reducing harmful battery waste*Works with virtually all replaceable battery types; alkaline, lithium, button, 1.5V – 12V*Fits battery sizes AAA – D, 12V, 9V, camera, watch & > read more

Wireless IR-RF Remote Repeater Kit

Published on 2011-06-03 01:57:25

Have you ever been frustrated with the range of your remote controls? Tired of having to bounce your IR remote off ceilings and walls? Do you want to run your system from another room or floor? This is the answer to your prayers! Extend the range of > read more

The Clapper Sound Activated On-Off Switch

Published on 2011-06-02 23:04:02

The sound activated on/off switch. With clap detection lights. 2 Claps turn on the lamp. 3 Claps turn on the TV. The Clapper can control one or two appliances at the same time. Set the dial to Home or Away. Connect your appliance(s) into The Clapper. > read more

Simple dc motor speed controller using quad NOR gate

Published on 2011-06-01 05:33:35

Here a quad NOR gate (IC1-CD4001) acts as a 50Hz astable multivibrator that generates a rectangular output. The mark-space ratio of the rectangular waveform is fully variable from 20:1 to 1:20 via potentiometer VR1. The output from the multivibrator > read more

Basic 12v Motor Speed Controllers using 2N3055

Published on 2011-06-01 05:22:55

Here are two simple 12V DC motor speed controllers that can be built for just a few dollars. They exploit the fact that the rotational speed of a DC motor is directly proportional to the mean value of its supply voltage. The first circuit shows how v > read more

Discrete PWM Generator Circuit

Published on 2011-05-30 06:16:50

PWM waveforms are commonly used to control the speed of DC motors. The mark/space ratio of the digital wave-form can be defined either by using an adjustable analogue voltage level (in the case of a NE555 based PWM generator) or digitally using binar > read more

DC Motor Speed Controller

Published on 2011-05-30 06:00:00

This circuit takes advantage of the voltage drop across bridge rectifier diodes to produce a 5-position variable voltage supply to a DC fan or other small DC motor. It is not as efficient as a switch-mode circuit but it has the virtues of simplicity > read more

Pump Controller For Solar Hot Water System

Published on 2011-05-28 20:24:02

This circuit optimises the operation of a solar hot water system. When the water in the solar collector is hotter than the storage tank, the pump runs. The circuit comprises two LM335Z temperature sensors, a comparator and Mosfet. Sensor 1 connects t > read more

Junk-box Fan Speed Controller using lm335

Published on 2011-05-28 20:05:24

My new home theatre receiver was getting rather hot in the close confines of its cabinet, with the temperature reaching over 40°C after only about 30 minutes of use. To help lower the temperature, I decided to install a fan in the cabinet. A 75mm ho > read more

12V Speed Controller and Halogen lamps Dimmer

Published on 2011-05-26 05:20:10

This handy circuit can be used as a speed controller for a 12V motor rated up to 5A (continuous) or as a dimmer for a 12V halogen or standard incandescent lamp rated up to 50W. It varies the power to the load (motor or lamp) using pulse width modulat > read more

Long-Interval Pulse Generator using LM3710 supervisor IC

Published on 2011-05-26 04:59:42

A rectangular-wave pulse generator with an extremely long period can be built using only two components: a National Semiconductor LM3710 supervisor IC and a 100-nF capacitor to eliminate noise spikes. This circuit utilises the watchdog and reset time > read more

1kH Synthetic Inductor using TL082

Published on 2011-05-26 04:46:57

Inductors can be mimicked quite easily using operational amplifiers. The circuit shown here was developed to have an inductance of 1000 H (say, one thousand Henry) with good damping. Using this design you can build a resonant circuit with a center fr > read more

ultrasonic dog whistle circuit

Published on 2011-05-25 06:34:28

It’s well known that many animals are particularly sensitive to high-frequency sounds that humans can’t hear. Many commercial pest repellers based on this principle are available, most of them operating in the range of 30 to 50 kHz. My ai > read more

automatic battery charger circuit

Published on 2011-05-25 06:15:59

The following automatic battery-charger design is created with a circuit that could qualify as the simplest window comparator ever built around a single transistor. It starts charging when the battery voltage drops beyond a preset value, and it stops > read more

Transcutaneous Electrical Nerve Stimulator

Published on 2011-05-24 02:43:48

A Transcutaneous Electrical Nerve Stimulation (TENS) device is, put bluntly, a machine for giving electric shocks. The author was prescribed such a device on loan by his orthopaedic specialist. The unit has a large number of programmes, of which he u > read more

Behringer 48V Phantom Power Supply

Published on 2011-05-24 01:07:24

Portable Power The PS400 features XLR THRU jacks and provides superb noise-free operation. Just connect your condenser mic to the MIC INPUT and send a line from the MIC THRU to your mixer. You can toggle between +12 V and +48 V power for maximum flex > read more

AM/FM Preamp Kit

Published on 2011-05-23 06:48:15

Amplify Those Signals! Designed specifically for AM/FM radio reception, the K2622 provides 22dB gain between 10MHz and 150MHz. The sleek metal housing provides the necessary shielding and assures you of the least amount of interference. Input power i > read more

IR 2 Channel Remote Receiver Kit

Published on 2011-05-23 06:28:09

Program Two Functions! Use the sleek K8049 as the main remote for your IR control. Perhaps add an automatic light dimmer with the K6712 above. But with 15 channels available on your remote youve got lots of control room to spare! This tiny little rec > read more

Tablet Reminder Uses Watch Module

Published on 2011-05-23 02:36:32

This device is used as a reminder to take medicine every day. This device actually contains a crystal watch and a 4001 quad 2-input NOR gate with two of the gates (IC1a & IC1b) wired as an RS flipflop. The watch is set to “tablet time̶ > read more

123 Game – All MCU-free (simple electronic game circuits)

Published on 2011-05-23 02:25:15

This electronic game pits a human player against the ‘machine’. The opponents use a common ‘game token’ and take turns moving along a path by one, two or three steps, and the winner is the first one to reach the goal exactly. Incredibly enoug > read more

RGB To Color Difference Converter

Published on 2011-05-23 02:11:56

The circuit diagram shows two LT1398’s from Linear Technology used to create buffered color-difference signals from RGB (red-green-blue) inputs. In this application, the R input arrives via 75? coax. It is routed to the non-inverting input of ampli > read more

Grand Prix Starting Lights using LM339

Published on 2011-05-22 08:57:01

This circuit reproduces the starting light sequence currently used by FISA for Formula One racing. It could be used with slot car sets (such as HO scale AFX/Life Like/Tyco sets) or radio controlled cars. IC1, a 555 timer IC, is used as a clock pulse > read more

El-Cheapo Fluoro Ballast

Published on 2011-05-21 07:50:29

This simple circuit can start small (15W or less) fluorescent tubes such as those used in PC board exposure and EPROM ultraviolet erasure boxes. As you can see, the tube’s filament heaters are not used. Instead, ignition is provided by a voltage tr > read more

Transistor quality checker with buzzer

Published on 2011-05-21 01:00:52

You checked the transistor by measuring the resistance between the different pins. Sometimes it has problems, such as when measuring the resistance between the various legs correctly. But it does not work in the real circuit. Because while there is n > read more

Telephone ringer light

Published on 2011-05-20 10:26:12

If you are lucky enough to have a big house, a large garden, and small children, this project just might interest you. It’s actually a telephone ringer capable of making any mains-powered device work from the ringer of your fixed line. With it, you > read more

Classic TV Pong Game Kit

Published on 2011-05-20 05:34:23

Build the classic pong game that started the video game revolution. Has composite video and audio outputs, adjustable brightness and auto power off. One and two player modes with four difficulty levels. Paddles controlled by buttons on the board. Pre > read more

Bulldog keyless entry system for cars

Published on 2011-05-20 05:09:58

The unit was easy to test and install and has a range of about 100 feet. For basic testing, temporarily connect the power and ground wires and listen to internal relay clicks while pressing lock and unlock buttons on one of the remotes. To get a good > read more

60 seconds Delay Timer Kit

Published on 2011-05-20 02:50:03

The ELK960 Delay Timer is designed to be an economical and flexible solution for any general-purpose timer application. The unit can be configured for use on 12 to 24V systems, with positive or negative trigger logic. Positive triggers can be as low > read more

1HZ Standard digital clock

Published on 2011-05-19 04:11:45

This is a standard digital clock circuit,frequency size 1 Hz or 2 Hz. It can be used in the normal clock circuit. It consists of IC-4060 and IC-4013, the IC-4060 single acting Oscillator and Counter. of the frequency determined by the resistor and ex > read more

Wireless Motion Alert Kit

Published on 2011-05-19 00:46:04

Don’t be caught unaware. Protect your home or business from unexpected visitors. The WMA Wireless Motion Alert system sends an immediate alert when a person or car enters your property. The transmitter operates on one 9V battery, is weatherproo > read more

Interval Timer kit

Published on 2011-05-19 00:24:34

For intermittent operation of circuits and equipment. Blinking light, video/photo single frame shooting, slide projector control, miniature models. Specifications: * Output relay with dry switch-over contact: 3A/24V * Pulse time adjustable: between 0 > read more

Electronic Circuits for the Evil Genius 2

Published on 2011-05-19 00:05:34

Teach or learn basic electronics in a hands-on and logical manner by: 1) Getting the book “Electronics Circuits for the Evil Genius 2E” by Dave Cutcher. 2) Getting this new and expanded custom electronic component kit tailored to the 2nd > read more

Temperature-Controlled Soldering Iron

Published on 2011-05-17 04:34:28

One reason why commercial soldering stations are expensive is that, in general, they require the use of soldering irons with inbuilt temperature sensors, such as thermocouples. This circuit eliminates the need for a special sensor because it senses t > read more

Coaxial cable tester circuit

Published on 2011-05-16 07:18:36

This is Coaxial cable tester circuit.It is useful to check the cables inside and outside. Check the continuity of the cable, check cable short-circuited. And detection of the high resistance of the cable. Check that all lamp displays with LED. Operat > read more

I want to buy multimeter

Published on 2011-05-16 06:39:36

The generally electronics worker has many tools. Multimeter is a tool that needs a lot, because a project electronics.Require a measure of electricity, such as measuring voltage, resistance measurement, power measurement, and other. I think to find o > read more

Digital Oscilloscope DIY Kit

Published on 2011-05-15 06:59:04

This kit includes everything you need to build your very own, fully functional, digital oscilloscope. Once you’ve got it up and running, the oscilloscope features up to 5M samples/second, 8-bit resolution, up to 50Vpp max input voltage, and mor > read more

Cheap siren with nand gate IC

Published on 2011-05-13 22:52:57

This is a siren sound generator circuit. Which is less expensive and can create simple. The IC1 is using CD4011 (Digital Nand Gate) and the IC2 is CD4046. Operation of the circuit, IC1 is a clock frequency 1 Hz.(Frequency adjusted by the value of R1 > read more

The level voltage of logic changer by a JFET

Published on 2011-05-13 08:41:41

This is a logic signal changer circuit,the normal voltage of about 5V. But sometimes we want to 12V or 15V, we can use a JFET.It works by mode COMMON GATE. Simple principle is that when a logic “0″ or 0V.The JFET N-channel type which will > read more

A diode protect cmos circuit

Published on 2011-05-13 04:05:29

The CMOS digital circuit used to produce a osicillator, with pulse low frequency frorm. We use R and C are a lot of period time. it must have a diode to prevent current flow feedback. In picture the oscillator circuit, we use the CD40106 and 74HCT132 > read more

Soil dry tester circuit

Published on 2011-05-12 20:08:38

This Check this dry soil circuit For the Blind. Because it will alert on clay. Circuit has less detail. It production the low frequency pulse, the IC CMOS 4001. is primary device,internal structure consists of NOR Gate.When added to RC circuit will b > read more

Neon Flasher Runs From 3V Supply

Published on 2011-05-09 05:38:34

A neon indicator typically requires at least 70V to fire it and normally would not be contemplated in a battery circuit. However, this little switchmode circuit from the Linear Technology website (www.linear-tech.com) steps up the 3V battery supply t > read more

Temperature monitor

Published on 2011-05-08 11:35:11

This temperature monitor circuit is used where a continous analog display of temperature value being monitored is not necessary. A simple indication whether the temperature value exceeded a maximum level or went below the minimum level is sometimes e > read more

Simple Micro Ampere Meter Circuit

Published on 2011-05-08 11:26:46

This simple micro ampere meter circuit can help in measuring small currents in five ranges: from 1 µA to 10 mA. The meter is working in this way: the current being measured Ix shifts the input voltage resulting to an output voltage with an inverted > read more

Increase output current of the op-amp IC LM324 in 85mA size

Published on 2011-05-07 06:29:17

The op amp output current can generally be in the range of 20 to 40mA.However, the LM324 IC number includes op amp 4 and 3 per parallel.Therefore the output currents up to 85mA, it also has significant short-circuit protection too. The properties of > read more

Make and Learning Electronics by Discovery

Published on 2011-05-07 03:41:04

This is Excellent Beginner Book for Hobbyists/Beginners/Makers Book. Want to learn the fundamentals of electronics in a fun, hands-on way? With Make: Electronics, you’ll start working on real projects as soon as you crack open the book. Explore > read more

Electronic Circuits for the Evil Genius

Published on 2011-05-07 03:27:48

Fully updated throughout, this wickedly inventive guide introduces electronic circuits and circuit design, both analog and digital, through a series of projects you’ll complete one simple lesson at a time. The separate lessons build on each oth > read more

Full wave rectifier with an op amp IC

Published on 2011-05-06 10:47:23

This circuit acts rectifier the ACV signal.This circuit usually requires two op-amp, but this circuit uses only one op-amp. The work is easy when a positive input into, The D1, D2 will does not work. The output is equal to R2 / (R2 + R3).When V1 is t > read more

Automatic Light Controller Using 7806

Published on 2011-05-04 10:36:41

Voltage regulator ICs (78xx series) provide a steady output voltage, as against a widely fluctuating input supply, when the common terminal is grounded. Any voltage about zero volt (ground) connected in the common terminal is added to the output volt > read more

Mains Powered White LED Lamp

Published on 2011-05-04 10:10:57

Did it ever occur to you that an array of white LEDs can be used as a small lamp for the living room? If not, read on. LED lamps are available ready-made, look exactly the same as standard halogen lamps and can be fitted in a standard 230-V light fit > read more

Passive Air Band Monitor

Published on 2011-05-04 08:11:53

This broadband radio monitors transmissions over the entire aircraft band of 118-136 MHz. The strongest signal within the pass band of the radio will be heard. The ABM1 has no local oscillator, it doesn’t, can’t, and won’t generate > read more

LED Dimmer PWM DC Lighting Dimmer Controller for LED Incandescent

Published on 2011-05-04 05:27:14

This self-contained 12 volt dimmer and on/off switch is designed for precise control of interior accent lighting in your auto, truck, RV, boat or aircraft. With a 1/4 shaft and easy screw-down terminals, you can install this controller in minutes. It > read more

Attenuate variable radio frequency

Published on 2011-05-03 11:52:54

This circuit can be designed to attenuate signal frequency. Customizable from 1 to 40 dB.If you want to use the band uhf, should be fitted within the frame shield, and C1 to C3 type feeds true.The line should be as short as possible, and the diode sh > read more

Electronic DC Motor Speed Controller Device Modulator 30 Ampere

Published on 2011-05-03 10:55:35

Use the LX066 to control the speed of your electric motor or brightness of a DC light bulb. Obtain low speed from a DC motor without sacrificing torque. The LX066 is a small assembled device with an on-board trim pot to control the pulse width modula > read more

Blinky Eyes Animated Display

Published on 2011-05-03 04:00:36

The ultimate animated LED kit that will dazzle you and delight your friends! Uses a microcontroller to randomly select from many different animations such as a long pause before a wink, or a twinkle of the eye to startle passers-by. … Read more > read more

Automatic Telephone Ringdown

Published on 2011-05-03 03:39:58

What is a telephone ring down, you may ask? They have been used for years as dedicated communications paths between two standard telephone sets. Over a single pair, with a phone at either end, merely going off hook with one phone immediately rings th > read more

9 Volt LED Flashlight kit

Published on 2011-05-02 11:25:09

Ever find yourself fumbling in the dark looking for keys or an item on the nightstand? Well this 9 Volt LED Flashlight by Kikkerland is a tiny treasure that will never leave you in the dark again. The simple yet unique invention combines LED technolo > read more

Simple compressor with 1N914

Published on 2011-05-02 00:25:54

This simple compressor circuit is suitable for use in a recorder tape from the speaker terminals of the receiver.This input can be changed from 200 mV to 6V. The output will remain at close to 5 mV. An attack time of the circuit for about 3 ms and re > read more

Microwave Motion Detector Kit

Published on 2011-05-01 01:06:20

The MD3C sends out a microwave signal and looks for a return. A moving object will reflect back some microwave energy and the kit detects it. Since microwaves (no, you won’t get cooked or burned by them!) are used – heat, light, sound or > read more

Laser Trip Sensor Kit

Published on 2011-04-30 22:22:52

For years hobbyists have been intrigued by the possibility of using a ‘beam of light’ to control other devices! The abundance of inexpensive laser elements that have now become available has further pushed the demand for useful products a > read more

Noise limiter signal

Published on 2011-04-30 08:33:54

Interference from ignition noise pulse of the engine, it can cause various problems associated with radio communication equipment installed in the car.This circuit improves signal to noise ratio (S / N-ratio) was better, To connected between the outp > read more

Simple AGC for radio receiver

Published on 2011-04-30 05:02:54

The automatic Gian control circuit also AGC with audio signal is simplest for compress to signal in the Radio receiver. It is ideal for short wave radio receiver used in areas with weak signals. You should adjust the master volume control dress until > read more

Repair Dell GX620 computer with myself

Published on 2011-04-27 11:08:11

I had been using Dell GX620 Computer for a long time because it has good and durability. I lost it some days ago. My friend who is a computer repairer said the power supply is having problem. He told me to buy it at amazon.com,they are very nice it h > read more

Automatic Plant watering reminder

Published on 2011-04-25 12:23:08

House plants in general often have a pretty hard time of it compared to their garden bound cousins, which seem to get more than their fair share of watering, even if their owner forgets, thanks to the British weather. With so many other things to thi > read more

Double signal with non linear characteristic

Published on 2011-04-22 11:43:23

This is a double frequency circuit, it was uses a non-linear characteristic of the transistor for Regutifier transistor to a half-wave rectifier. The resistor R1 is the feedback control, fine-tune the output waveform is purity. > read more

60 Watt Solar Charging Kit

Published on 2011-04-19 12:02:22

I’m do looking to backup energy for my laptop, The 60 Watt Solar Charging Kit is need for me very much, it low cost but Good quality,saving money very much,…. Read more Example review I can run my laptop all day, as well as recharge the c > read more

Very cheap ac light dimmer

Published on 2011-04-18 11:30:56

You may had saw to a complicated AC light dimmer circuit ago. Now let’s look simple, but useful, fairly good. This circuit uses a capacitor in series with one lamp and accessories with a bit more. Is used to control the light dimmer, Easy and c > read more

Voltage to current using op-amp and power transistor

Published on 2011-04-13 10:00:49

This circuit changes the voltage to current, can provide dc current characteristics and AC so-so Circuit consists of 3 op-amps, 2 transistors is moderate. Passive devices and only a little. This circuit with grounded. load, it controls the rate Vout > read more

Digital Dice circuit

Published on 2011-04-11 10:08:25

A electronic friends was seeking a play circuits in your free time,a cheap and easy to made.This dice digital circuit would be a favorite of everyone, by using it to display the numbers. When you switch to a spin button or it like is tossing a dice. > read more

The transistor lat

Published on 2011-04-10 10:03:57

This circuit, it works similar to a SCR.When the trigger input is high, The transistor Q2 and Q1 will work,therefore a current flow to the base pin of Q2,it has voltage 0.7 volts at resistor R1. When cutting the activation voltage, the transistors ca > read more

High impedene small amplifer circuit

Published on 2011-04-09 12:52:27

This simple circuit was a presented,it can give power output about 1 watt, when connected to a power supply 9 volt. The advantage of this circuit is that it uses a dual darling ton to increase the size as much as of input impedance about 20 Meg ohm. > read more

Easy dry cell charger with CMOS IC 4011

Published on 2011-04-09 09:47:23

The dry cell charger circuit can be fully charged about 12 hours.When used with a 9 volt supply,the equipments in the circuit for the AA type cell.When using the C and D type cell, should reduce the value of the resistance Rx to be 68 ohms.In charge > read more

Alarm sound with control switch.

Published on 2011-04-08 06:49:35

The heart of this circuit is IC No. 555. When the alert sound was working, even though the switch will continue to be the same, the sound still does not stop immediately.But it will stops automatically, when a set time period,Depending on the resista > read more

The best electronic switch

Published on 2011-04-05 12:44:20

This switches circuit,It can be useful many things.which a output of the circuit can be controlled a bell or other sound source circuit or control relay or SCR.(a circuit for RY1,and SCR2 are used with AC voltage source only) The contact switches (S1 > read more

Headlight Warning Buzzer

Published on 2011-04-04 10:13:03

Often,we find that a lot of motorist.They have forgotten to turn on light in a car when parking.then back to start the machine,it did not work,because a battery did not have a energy. but this circuit will be warning a car driver for instantly know,w > read more

Automatic watering a tree

Published on 2011-04-02 08:04:20

A trees should be taken care of as well. This circuit allows for watering trees, can be done automatically.When soil moisture levels decrease, to values that are defined.(Which can be determined by the resistance of R1.) A relay RY1 starts.This relay > read more

Simple Cat.5 Network Tester

Published on 2011-03-31 11:52:14

This circuit came from a need for a “quick and dirty” network tester that could be operated by one person. All the commercial units I tried required a person at the other end to check the remote LEDs, as the transmitters could not be made > read more

Easy add value capacitance

Published on 2011-03-29 08:32:23

Some circuit we need to use very high value for the capacitance value of capacitors.For example filter circuit etc. This circuit add capacitance, can use instanced of an difficult which is expensive or very high value. This circuit was analyzed from > read more

Easy Power supply for cassette player

Published on 2011-03-25 20:52:01

This circuit that you see, It is an one style of an easy simple power supply, for a recorder or a cassette player in the car which used voltage 12V.It is only using the current abount 100mA. When it occured over load current at output.it will not dam > read more

Body Charge Detector

Published on 2011-03-24 08:45:05

It is well known that through such simple everyday activities as walking on a carpet or moving in a chair, the body accumulates a static charge – sometimes many thousands of volts. Due to its extreme sensitivity, this circuit will detect not on > read more

Simple Amplifier circuit for converts the analog signal to digital

Published on 2011-03-23 04:45:33

The electrical signals from transducer,Sometimes, it is value less too,For input to the circuit to convert signals from analog to digital.To achieve a satisfactory,We need a power amplifier, who can tell strength of the input signal is simple.This ca > read more

Invisible Broken Wire Detector

Published on 2011-03-22 12:44:28

Portable loads such as video cameras, halogen flood lights, electrical irons, hand drillers, grinders, and cutters are powered by connecting long 2- or 3-core cables to the mains plug. Due to prolonged usage, the power cord wires are subjected to mec > read more

Low Supply Rail Detect voltage

Published on 2011-03-22 12:25:56

Here’s a simple low supply rail detection circuit that costs peanuts and takes just 20 minutes or so to make. Its power consumption is quite low, so it could easily be built into battery-powered devices. Instead of using an op amp, the circuit > read more

Video Tracer For Trouble-Shooting

Published on 2011-03-19 04:04:18

This circuit was designed as an aid to installers and maintainers of video systems. It is basically a video sync separator (IC1) followed by a LED and buzzer driver (IC2, Q1 & Q2). In use, the device is connected to a video cable and if there is > read more

NTSC-PAL TV Signal Identifier

Published on 2011-03-19 03:50:37

This circuit is able to identify PAL and NTSC video signals. Its output is high for an NTSC signal and low if the signal is PAL. This output signal can be used, for example, to automatically switch in a colour subcarrier converter or some other devic > read more

Video Amplifier using BC560

Published on 2011-03-19 03:42:13

The video amplifier in the diagram is a well-known design. Simple, yet very useful, were it not for the ease with which the transistors can be damaged if the potentiometers (black level and signal amplitude) are in their extreme position. Fortunately > read more

On And Off Button

Published on 2011-03-19 03:29:51

In this simple circuit we give the chip a little more attention than usual. It is astonishing what can be built with a 555. We are always infatuated with simple circuits using this IC, such as the one shown here. The 555 is used here so that a single > read more

One Of Nine Sequencer

Published on 2011-03-16 21:21:14

This novel circuit uses a flashing LED as the clock input for a 4017 decade counter. Typical flashing LEDs (eg, DSE cat Z-4044) flash at about 2Hz so the outputs Q0-Q9 will cycle through at that rate. For example, Q0 will turn on for half a second, t > read more

Voice logic probe by transistor BC557

Published on 2011-03-15 23:27:28

The key is that the logic probe circuit, using a light emitting diode, or LED display is a state (high or low) point of the analysis, but on the other hand, it can display the state has the same voice. The circuit is shown, it is the audio source, cl > read more

Push Off Push On

Published on 2011-03-15 23:03:52

The ubiquitous 555 has yet another airing with this bistable using a simple push-button to provide a push-on, push-off action. It uses the same principle of the stored charge in a capacitor taking a Schmitt trigger through its dead-band. Whereas the > read more

Micro Maestro 6-channel USB Servo Controller

Published on 2011-03-15 22:56:49

The six-channel Micro Maestro raises the performance bar for serial servo controllers with features such as a native USB interface and internal scripting control. Whether you want high-performance servo control (0.25?s resolution with built-in speed > read more

Regulator to improve better

Published on 2011-03-15 10:03:14

In some special applications, required supply voltage, which is very accurate, and It looks like, how popular each one. Then, to improve the output voltage of voltage regulator better. With “improve” the Commonwealth, (that is to increase > read more

Pushbutton Relay Selector

Published on 2011-03-15 08:33:41

This circuit was designed for use in a hifi showroom, where a choice of speakers could be connected to a stereo amplifier for comparative purposes. It could be used for other similar applications where just one of an array of devices needs to be sele > read more

Basic electronics parts set

Published on 2011-03-13 09:34:41

In the past I have experienced problems with electronic devices, hard to find, expensive, and there is no end equipment. I like Elenco – Basic Parts Set, because it helps to solve this problem. It is ideal for all basic electronics. More inform > read more

Internal Resistance Tester For Batteries

Published on 2011-03-13 03:47:14

This circuit is designed to check the condition of lead-acid and gel cell batteries with capacities greater than 20Ah. It switches a load of about 18A at a rate close to 50Hz so that the internal resistance of the battery can be measured using a digi > read more

Pump it up Mp3 Booster

Published on 2011-03-13 03:43:24

MP3 players are all the rage these days. The smaller ones in memory-stick format are particularly easy to take with you; your very own ‘personal sound system’ on the move! It’s when you want others to share your taste in music that you ?nd thes > read more

Mini Logic probe with transistor circuit

Published on 2011-03-11 04:52:56

This is a Logic probe circuit is one,That is suitable for checking the voltage levels in the TTL circuit. It receives from the circuit being tested.Shows how high or low logic level one. The circuit when the input voltage to the probe Tip is higher t > read more

Oscillator astable multi-vibrator with Crystal controller

Published on 2011-03-10 07:34:34

Oscillator circuit of this nature.Often used as a clock circuit.This circuit uses a million crystal frequency control with stability.And a circuit that does not use the capacitor or Inductor all. Each transistor to work, the amplifier with feedback. > read more

Actron CP9580 Auto Scanner with CodeConnect

Published on 2011-03-10 03:40:23

The Actron CP9580 AutoScanner Plus OBD II, CAN & ABS Scan Tool is the ultimate choice in handheld automotive diagnostic scan tools, suitable both for advanced automotive do-it-yourselfers (DIYers) and automotive professionals alike. Not only doe > read more

Resonance generators by 4011 CMOS Gate

Published on 2011-03-09 05:13:49

This Resonance generators (oscillating sound generator) circuit, designed using CMOS integrated circuit number 4011(CMOS Quad 2-Input NAND Gate). Contains within 4 nand gate. To each oscillator circuit has a 2 circuit.This circuit provides a higher f > read more

Pipe Descaler

Published on 2011-03-09 01:08:45

For many years now, magnetic (or electromagnetic) water descaler devices have been showing up on the shelves of Home Improvement and other DIY stores all over Europe. Despite the numerous studies completed on that subject, by manufacturers as well as > read more

Bosch PS30-2A 12-Volt Max 3/8-Inch Drill Driver

Published on 2011-03-08 19:04:01

Bosch PS30 – 2A 12 – Volt Max 3/8-Inch Driver Drill speed, power, and performance in a package compact portable. This powerful easy-to-use drill / driver features two three-speed head, jaw and efficient design, durable packs punch by main > read more

MAXSA Innovations 40218 Motion-Activated Dual Head LED Security Spotlight

Published on 2011-03-08 18:53:50

This is one of the brightest solar-powered, motion-activated outdoor security spotlights on the market. Reposition the heads for wide illumination. The LEDs never burn out or need changing. This environmentally friendly unit ensures that you always h > read more

Safety Guard by CD4060

Published on 2011-03-06 23:49:43

Simple unit, Protects home appliances from voltage spikes Protect your home appliances from voltage spikes with this simple time delay circuit. Whenever power to the appliances is switched on or resumes after mains failure, the oscillator starts osci > read more

Streamlight 88031 Protac Tactical Flashlight 2L with White LED

Published on 2011-03-06 06:05:56

Streamlight Professional Tactical 2L LED Flashlight is an ultra compact tactical light by Streamlight. The Streamlite Professional Tactical 2L is a small C4 LED Flashlight and one of the brightest tactical personal carry lights for its size. The Stre > read more

Simple slant (tilt) alarm switch circuit

Published on 2011-03-06 00:33:49

This is a simple alarm circuit.This work, when the switch S1 (sensor) tilted away from vertical.The alarm stops when the sensor back to the old form. S1 sensor is a mercury switch.Contact is a normal closed.When the switch is placed in a vertical.Tra > read more

Very simple voltmeter with ic741

Published on 2011-03-05 23:30:22

This circuit can be used to measure the voltage to 15 volts.Using the current from the battery 9 volt,At 23 mA only. Input circuit has a diode, to protect the Return terminal. And input impedance of the circuit, were more than 1 M ohm. Heart of the c > read more

Advanced 500 In 1 Electronic Lab

Published on 2011-03-05 10:06:01

We went one (or rather, 200!) steps beyond our 300 in one lab kit! Yes, 500 in one, PLUS comprehensive learning course manuals! Build 500 exciting projects, learn schematics, build and learn both analog and digital circuits, and even get into digital > read more

booster 10,000x by One Transistor

Published on 2011-03-05 04:00:39

For a collector follower with emitter resistor, you’ll often find that the gain per stage is no more than 10 to 50 times. The gain increases when the emitter resistor is omitted. Unfortunately, the distortion also increases. With a ubiquitous trans > read more

Sound pressure meter

Published on 2011-03-04 22:35:20

Here is a simple circuit that can be used to check the sound levels.The sound pressure meter is vey useful in setting up home theater systems , if you need to test the sound pressure of each channels on different positions in the room. The circuit is > read more

Water Pump Relay Controller Circuit Schematic

Published on 2011-03-04 18:57:09

Water reservoir automatic level control Simple circuitry – 12V supply Device purpose: By means of a Relay, employed to drive a water pump, this circuit provides automatic level control of a water reservoir or well. Circuit operation: The shorte > read more

A frequency multiplier in depth

Published on 2011-03-04 10:19:35

Most of the frequency multiplier circuit using IC phase locked loop (PLL).It will increase the frequency to an integer only. But this circuit can double the frequency, in the integer to a fractional number.This circuit has an IC phase locked loop num > read more

Led light bar scan back and forth led two color

Published on 2011-03-03 00:07:07

This circuit is a circuit run on alternating two colors.It uses the 2-color LED with a built-in 3-pin single.This will chase away the glow of each LED until the end.It turns alternating to another color.In any way to the moon on the moon first end, t > read more

Midnight Security Light Circuit Schematic

Published on 2011-03-01 05:55:44

Most thefts happen after midnight hours when people enter the second phase of sleep called ‘paradoxical’ sleep. Here is an energy-saving circuit that causes the thieves to abort the theft attempt by lighting up the possible sites of intrusion (su > read more

Battery Tester For Deaf and Blind Persons

Published on 2011-02-28 07:01:48

Many blind and deaf-blind persons use portable electronic devices to assist their everyday lives but it is difficult for them to test the batteries used in this equipment. Talking voltmeters are available but there is no equivalent usable by deaf-bli > read more

Remote Control Mains Switch

Published on 2011-02-26 18:48:56

As the only electronics engineer in my family and circle of friends, it is sometimes not possible to evade an appeal for help. This time the request came from a friendly elderly lady in a retirement home. In her room the light switch by the door and > read more

Relay Coil Energy Saver

Published on 2011-02-26 18:47:12

Some relays will become warm if they remain energized for some time. The circuit shown here will actuate the relay as before but then reduce the ‘hold’ current through the relay coil current by about 50%, thus considerably reducing the amount of > read more

Automatic Switch For Voltage Converters

Published on 2011-02-25 22:01:08

New applications for DC voltage converters, such as the ‘workhorse’ LT1070, arise every day. These converters can be adapted to nearly every imaginable ratio of input and output voltages. However, all of these circuits and devices have the same s > read more

Smoke Alarm Battery Life Extender

Published on 2011-02-25 21:58:40

While smoke alarms are quite cheap devices, the cost of 9V batteries quickly exceeds their purchase price. Added to that is the irritation of random beeps from the alarm as the battery reaches the end of its useful life. This circuit allows typical s > read more

A Very Simple LED Tester

Published on 2011-02-25 17:31:36

This simple LED tester consists of a current source with a potentiometer that can be used to adjust the current. The current source is implemented using a type TL081 opamp. The output current of the opamp flows through the diode and R2. The voltage d > read more

IR Remote Control Tester

Published on 2011-02-24 22:32:30

This small circuit is ideal for checking the basic operation of an infrared remote control unit. The circuit is based on the brilliantly simple idea of connecting a piezo buzzer directly to an IR receiver IC. This method is almost as simple as connec > read more

Romantic Rose USB 2.0 4-Port Ultra Mini Hub, Red Base

Published on 2011-02-24 21:53:14

There are a lot of USB 2.0 hubs out there, but none of them are as cute as this one. It is not only a hub, but also a perfect ornament for your room. * Offers lightweight, compact design-perfect for travel * Installs with Plug-and-Play ease-requires > read more

Portable Lamp Flasher

Published on 2011-02-23 22:05:35

Here is a portable, high-power incandescent electric lamp flasher. It is basically a dual flasher (alternating blinker) that can handle two separate 230V AC loads (bulbs L1 and L2). The circuit is fully transistorised and battery-powered. The free-ru > read more

Laughing Faces USB 2.0 4-Port Ultra Mini Hub

Published on 2011-02-23 18:47:39

There are a lot of USB 2.0 hubs out there, but none of them are as cute as this one. It is not only a hub, but also a perfect ornament for your room. * Offers lightweight, compact design-perfect for travel * Installs with Plug-and-Play ease-requires > read more

Photo Picture Frame with Digital Recorder

Published on 2011-02-23 18:46:56

This photo frame with built-in digital recorder is the perfect gift for any occasion, or buy one for yourself! Records and stores audio messages for up to 100 years. Easy operation: just print and insert your photo in the frame and record your person > read more

LED Tester Circuit Diagram

Published on 2011-02-23 18:46:32

You have to admit that these tiny electronic lamps are handy, and they last almost forever. Around 40 years after Nick Holanyak developed the first LED, they have become just about indispensable. Any self-respecting electronics hobbyist always has a > read more

Bell Alarm

Published on 2011-02-23 07:59:38

If you use a lamp with a motion sensor for outdoor lighting, the original electrical switch is actually no longer necessary. If you replace the switch with the circuit described here, an acoustical signal will be generated each time the outdoor lamp > read more

Safe Oscillator For Watch Crystals

Published on 2011-02-23 02:00:35

This circuit was developed to allow watch crystals to be used in an existing CMOS oscillator circuit that was to run from a 12V supply. The problem is that these crystals only work up to a supply voltage of about 6V. Any more than that and the crysta > read more

Components Voltage Tester Circuit Schematic

Published on 2011-02-23 00:32:16

This simple circuit tests speakers, microphones, transformers and voltage. It’s basically a very low frequency oscillator that produces extremely short ‘fruity’ pulses. The type of sound produced is very easy to hear and to determin > read more

Xacto X75170 X-tra Hands with Magnifier

Published on 2011-02-22 23:40:34

The X-TRA Hands dual alligator clamps with 2X magnifying glass by X-ACTO is the perfect solution for any hobbyist or designer who needs a second set of hands to hold onto materials. These clamps will hold your work firmly in position, freeing your ha > read more

Puchi Puchi Electronic Bubble Wrap Packaging Key Ring

Published on 2011-02-22 23:38:52

Puchi Puchi Electronic Bubble Wrap Key Ring Praised by Jonathan Ross on his show, he actually said its “..the greatest thing Ive ever owned…Isnt that the greatest thing you have ever seen in your entire life?” to see the video pleas > read more

Smooth & Silky Ultra Shaver, Rechargeable

Published on 2011-02-22 23:36:31

Remington’s WDF-1600 has convenient and comfortable electric shaving with Body Contour SafescreensTM that hug your curves for quick, close, comfortable results. It features 2 SafescreensTM Protect your skin from nicks and cuts, 1 SmoothCutTM tr > read more

Timer control 1-15 minutes by Triac 2N6075 and LM555-LM358

Published on 2011-02-22 00:37:00

Most timer circuits. Often used with electrical transformers containing low as 9V and 12V, and use of electrical control relays.but the 1-15 minute timer circuit.It uses a triac instead of electrical control.This can be used with a 220V power house i > read more

Clap-Controlled Switch

Published on 2011-02-21 23:21:22

This circuit can switch two or more devices on and off in response to a series of rapid handclaps. The claps are picked up by an electret microphone and amplified by a 741 op amp (IC1). IC1 is configured as an inverting amplifier, with its gain and h > read more

Electronic Touch Switch

Published on 2011-02-21 22:42:04

Mechanical contacts have the disadvantage that they wear out. That is why it is practical to use an electronic ‘touch switch’ in some situations. With such a touch switch the resistance of the human skin is used for the switching action. The sche > read more

Auto Power Off

Published on 2011-02-21 22:38:09

We are surrounded by battery operated equipment of all kinds, and this array is growing still. Manufacturers and designers lean over backwards to make sure that their equipment draws a small current and can thus be operated by a battery. This has its > read more

Weller SP23LK Marksman 25 Watt Soldering Iron Kit

Published on 2011-02-21 21:09:29

The Weller SP23LK Marksman 25-Watt Soldering Iron Kit has everything you need to get started soldering. An ideal choice for hobbies, crafts, and small electronics work, the kit contains a soldering iron, stand, nickel-plated tips, solder, and solderi > read more

Water Alarm Circuit Diagram

Published on 2011-02-21 21:05:50

Have you ever seen the stairs to one of the upper stories in your house turn into a waterfall? Or maybe you’ve come home to find your aquarium fish trying to swim across the carpet? For your sake, we hope not, because the consequences are usually f > read more

Remote Alarm For Smoke Detector

Published on 2011-02-21 10:15:04

This alarm circuit was designed to monitor a mains-powered smoke detector located in a shed (which is used to house dog kennels). It provides complete isolation from the mains so that low-voltage (12V) cabling could be run to the alarm circuit which > read more

Mains Supply Failure Alarm

Published on 2011-02-21 10:05:22

Whenever AC mains supply fails, this circuit alerts you by sounding an alarm. It also provides a backup light to help you find your way to the torch or the generator key in the dark. The circuit is powered directly by a 9V PP3/6F22 compact battery. P > read more

Flashing-LED Battery-status Indicator

Published on 2011-02-21 08:41:33

Signals when an on-circuit battery is exhausted 5V to 12V operating voltage A Battery-status Indicator circuit can be useful, mainly to monitor portable Test-gear instruments and similar devices. LED D1 flashes to attire the user’s attention, s > read more

Car and Motorcycle Battery Tester

Published on 2011-02-21 00:56:19

Going camping nowadays involves taking lots of electronic equipment whether for day to day running or for fun and entertainment. Most of the time a charged lead acid battery and a power inverter would be used to ensure a smoothly organized holiday wh > read more

Automatic Low-Power Emergancy Light

Published on 2011-02-20 23:46:24

Portable, simple and inexpensive unit, Useful for personal use Here is a white-LED-based emergency light that offers the following advantages. 1-It is highly bright due to the use of white LEDs. 2-The light turns on automatically when mains supply fa > read more

Belkin Pivot-Plug Surge Protectors

Published on 2011-02-20 22:58:27

You’ve got a lot of money invested in your home computer and peripherals, so you need to protect them. The Belkin BP112230-08 12-Outlet Pivot-Plug Surge Protector, with its unique rotating outlet design, is built to give you the peace of mind y > read more

Hello Kitty Bracelet Walkie Talkie Set

Published on 2011-02-20 21:56:50

These Hello Kitty Bracelet Walkie Talkies can be camouflaged as bracelets so you can secretly talk to your friends. Requires (4) pcs each: AG13/LR44 1.5V Button Cell Batteries (INCLUDED) Ages 5+. Read more > read more

On Off Touch Switch Circuit

Published on 2011-02-20 21:40:06

Small and portable unit, Suitable for normal-type devices The modern mechanic switches are improved concerning of old technology. We need however many times to replacement some old switch or to check currents bigger than the durability of certain swi > read more

10 LED roulette with TC4011-LM4017

Published on 2011-02-20 03:15:49

When entering the power supply circuit, and switch S1 (Start), which is attached press release switch off.Then current is flowing through R1, R2, and C2. Makes the capacitor C2 caused up When the switch S1 allows the C2 to discharge through R3. The p > read more

Smooth Flasher Circuit Diagram

Published on 2011-02-19 23:35:10

Ordinary LED flashers turn the LED on and off abruptly, which can get a little irritating after a while. The circuit shown here is more gentle on the eyes: the light intensity changes very slowly and sinusoidally, helping to generate a relaxed mood. > read more

LCD Weather Station and AM/FM Stereo Radio with Talking Alarm Clock

Published on 2011-02-19 20:42:25

AM/FM Clock Radio Digital Tuning System (DTS) AM/FM Sleep Timer Wake-up Radio Alarm Program Radio Channel Settings (Memory Set) Calendar 12/24 Clock Temperature/Weather Center Display Indoor Temperature Display Outdoor Temperature (one RF 433 MHz out > read more

Arduino UNO

Published on 2011-02-19 20:39:48

Before I bought this unit, I had never used an independent micro-controller. I used digital IO boards years ago while in college but those were always connected to a computer. I needed a self contained unit for a project and found a lot of recommenda > read more

Continuity Tester Circuit Diagram

Published on 2011-02-19 20:36:46

Having good contacts is important – not only in your daily life, but also in electronics. In contrast to social contacts, the reliability of electrical contacts can be checked quickly and easily. Various types of continuity testers are commercially > read more

Digital temperature sensor

Published on 2011-02-19 07:41:30

Here is a straight forward ,yet effective digital temperature controller that can be used with temperature control systems. The circuit uses IC LM35 (IC3) to sense the temperature.The output of LM35 is given to the IC ADC0804 (IC4) which converts the > read more

220Vac Lamp Toggle Switch

Published on 2011-02-19 07:35:34

Compact, transformerless circuitry No relays employed Due to the low current drawing, the circuit can be supplied from 230Vac mains without a transformer. Supply voltage is reduced to 12Vdc by means of C1 reactance, a two diode rectifier cell D1  > read more

Temperature Sensitive Switch For Solar Collector

Published on 2011-02-19 01:10:20

This circuit can be used to turn the pump on and off when a solar collector is used to heat a swimming pool, for example. This way the water in the collector has a chance to warm up significantly before it is pumped to the swimming pool. A bonus is t > read more

Slave Flash Trigger

Published on 2011-02-18 22:39:48

The flash that is built into digital cameras is designed for indoor photography. At subject distances of greater than five meters or so, the light is usually not powerful enough to take a satisfactory picture. Unfortunately most such cameras do not i > read more

Fully Automatic Emergency Light

Published on 2011-02-18 22:14:48

This simple automatic emergency light has the following advantages over conventional emergency lights: 1. The charging circuit stops automatically when the battery is fully charged. So you can leave the emergency light connected to AC mains overnight > read more

AmazonBasics USB 2.0 A-Male to A-Female Extension Cable

Published on 2011-02-18 20:49:08

The AmazonBasics USB 2.0 A-Male to A-Female Extension Cable with Gold-Plated Connectors lets you extend your USB connection by 9.8 feet and offers full performance for all your USB devices. If you need a longer USB 2.0 cable to connect a peripheral t > read more

Midnight Security Light Circuit Schematic

Published on 2011-02-18 11:20:03

Most thefts happen after midnight hours when people enter the second phase of sleep called ‘paradoxical’ sleep. Here is an energy-saving circuit that causes the thieves to abort the theft attempt by lighting up the possible sites of intrusion (su > read more

Cell Phone Signal Booster Kit for Vehicle w, Low Profile Antenna – for Multiple Users

Published on 2011-02-18 11:17:04

Increase your cell phone’s signal by up to 25 times with the Wilson Cell Phone Signal Booster Kit. Designed for use in your car, truck, RV, or boat, the booster kit significantly improves your cell phone’s performance and signal strength. > read more

Dancing LEDs

Published on 2011-02-18 11:15:56

LED sequencer: follows the rhythm of music or speech 9V Battery-operated portable unit The basic circuit illuminates up to ten LEDs in sequence, following the rhythm of music or speech picked-up by a small microphone. The expanded version can drive u > read more

RC (Remote Control) Switch with TLC555

Published on 2011-02-18 03:05:48

It is sometimes necessary for an RC (remote control) model to contain some kind of switching functionality. Some things that come to mind are lights on a model boat, or the folding away of the undercarriage of an aeroplane, etc. A standard solution e > read more

Snap Circuits RC Rover

Published on 2011-02-18 02:48:49

Simple, Fun Projects Let Kids Learn While They Play With its easy-to-follow instructions, Snap Circuits gives your child a hands-on education in how electrical circuits work to run their rover and the everyday devices that they’re familiar with > read more

Snap Circuits FM Radio

Published on 2011-02-18 02:41:11

Elenco’s Snap Circuits makes learning electronics easy and fun! Just follow the colorful pictures in our manual and build exciting projects such as AM radios, burglar alarms, doorbells and much more! You can even play electronic games with your > read more

IR Remote-Control Checker

Published on 2011-02-18 00:02:39

Suitable for any Infra-red emitting device 3V battery supply A very simple device allowing a quick check of common Infra-red Remote-Controls can be useful to the electronics amateur, frequently asked to repair or test these ubiquitous devices. A reli > read more

Switchable Output Crystal Oscillator

Published on 2011-02-17 21:59:08

This oscillator circuit permits crystals to be electronically switched by logic commands. The circuit is best understood by initially ignoring all crystals. Furthermore, assume that all diodes are shorts and their associated 1kO resistors open. The t > read more

Computer Data Cable Tester

Published on 2011-02-17 21:57:33

You don’t need access to fancy test gear to check and fault-find computer data cables. Instead, this simple device will give a quick indication of the status of point-to-point cable wiring; ie, crossovers, shorts and open circuits. It works lik > read more

High impedance DC voltmeter.

Published on 2011-02-17 21:53:49

A high impedance DC voltmeter using a uA741 IC is shown here. The operational amplifier is used as a non-inverting DC amplifier in which the negative feedback is through a DC meter requiring 1mA for full scale deflection. Since R6 is 100 Ohms, the me > read more

Fridge door Alarm

Published on 2011-02-17 09:42:34

Beeps if you leave open the door over 20 seconds 3V battery operation, simple circuitry This circuit, enclosed into a small box, is placed in the fridge near the lamp (if any) or the opening. With the door closed the interior of the fridge is in the > read more

Cheap AC Current Measurement

Published on 2011-02-17 09:39:05

The easy way to measure high AC currents is to use a clamp meter but these are generally quite expensive and cost several hundred dollars at a minimum. Add-on clampmeter adaptors can work well but they only work with digital multimeters which have mi > read more

Arduino Duemilanove

Published on 2011-02-17 09:26:15

Arduino 2009 board is very good for learning microcontrollers. Because everything is ready, available. Easy to use, connects to PC via USB, uses Java technology efficiently. Hundreds of projects available FOR FREE, since it is OPEN SOURCE. A. Andreat > read more

Water-level Alert

Published on 2011-02-17 00:54:55

Beeper or flashing LED alert 1.5V battery powered portable unit This circuit will emit an intermittent beep (or will flash a LED) when the water contained into a recipient has reached the desired level. It should be mounted on top of the recipient (e > read more

Fire Alarm Using Thermistor

Published on 2011-02-17 00:45:24

Small and simple unit, Can be used for Home-Security purpose In this fire alarm circuit, a Thermistor works as the heat sensor. When temperature increases, its resistance decreases, and vice versa. At normal temperature, the resistance of the Thermis > read more

Low Ohms Adaptor For DMMs Based On An LM317 Regulator

Published on 2011-02-16 21:48:16

This adaptor circuit is essentially a 100mA constant current source. It is applied across a low-value resistor of unknown value (ie, the resistance to be measured) and the resulting voltage drop can then be measured by a digital multimeter (DMM). Set > read more

Simple Logic Probe

Published on 2011-02-16 21:13:13

This simple logic probe has both LEDs on with no signal at the input but due to the nor gates connected to the probe, indicates correctly when a high or low signal is present. It also works correctly for pulse trains. Normally both LEDs are forward b > read more

Hyper-Simple Battery Capacity Tester

Published on 2011-02-16 09:59:17

The circuit described here is eminently suitable to indicate the capacity of a battery. We use a cheap electric clock for this. By connecting a resistor across the battery terminals, the battery is discharged somewhat faster than with the clock alone > read more

Harmonic Generator With Single Opamp

Published on 2011-02-16 09:55:37

Quartz crystals have the property that their amplitude/phase characteristic repeats itself at frequencies that are an uneven multiple of the fundamental frequency. There are so-called overtone crystals that are cut in such a manner that they possess > read more

IC Controlled Emergency Light With Charger Circuit

Published on 2011-02-16 08:39:02

Here is the circuit diagram of IC Controlled Emergancy Light With Charger or simply 12V to 220V AC inverter circuit. The circuit shown here is that of the IC controlled emergency light. Its main features are: automatic switching-on of the light on ma > read more

High-intensity LED Warning Flasher

Published on 2011-02-16 01:01:47

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 u > read more

12V Dimmer

Published on 2011-02-16 00:58:11

A dimmer is quite unusual in a caravan or on a boat. Here we describe how you can make one. So if you would like to be able to adjust the mood when you’re entertaining friends and acquaintances, then this circuit enables you to do so. Designing a d > read more

Ultra Bright LED Lamp for AC230V

Published on 2011-02-16 00:53:10

This ultra-bright white LED lamp works on 230V AC with minimal power consumption. It can be used to illuminate VU meters, SWR meters, etc. Ultra-bright LEDs available in the market cost Rs 8 to 15. These LEDs emit a 1000-6000mCd bright white light li > read more

Battery Tester Circuit Schematic

Published on 2011-02-15 07:36:08

Is the battery empty, or is there something wrong with the device? That’s always a difficult question when your walkman or some other battery-powered device appears to be dead when you switch it on. Before you take it to the shop for servicing, the > read more

Put That Light Out

Published on 2011-02-15 06:52:47

If you forget to switch off the light after leaving a seldom used room (such as the loft), there’s a strong likelihood that it could remain lit for months, running up an expensive power bill in the process. How can we prevent this waste? It’s not > read more

USB Experimenter’s Interface Board

Published on 2011-02-15 06:19:15

Not so long ago the universal answer for external control from a PC was the serial port. It was easy, it was simple, and you really couldn’t mess anything up! Then came parallel port outputs for higher speed connections and transfers. What came > read more

Two wire Lamp Flasher using BD139

Published on 2011-02-15 00:48:43

Ideal to operate 3 to 24V DC existing on-circuit lamps This circuit was designed to provide that continuous light lamps already wired into a circuit, become flashing. Simply insert the circuit between existing lamp and negative supply. Especially sui > read more

MAKE: Electronics: Learning Through Discovery

Published on 2011-02-15 00:42:21

Build working devices, from simple to complex You’ll start with the basics and then move on to more complicated projects. Go from switching circuits to integrated circuits, and from simple alarms to programmable microcontrollers. Step-by-step i > read more

Getting Started With Arduino book parts pack

Published on 2011-02-15 00:40:28

This pack contains the parts needed to try the exercises listed in the Getting Started with Arduino book. It includes a mini breadboard, LEDs, a DIODE, a TRANSISTOR, RESISTORS, a SWITCH and LDR. It tries to match the components listed and used in the > read more

Love test game circuit by 8 LED

Published on 2011-02-14 18:21:13

This circuit uses the nand gate IC number is 4011B per Clock signal generator circuit, feeding it with the pin number 14 of the IC counter circuit 4017B.When you press and hold the switch S1 C1 will discharge. Causing current flow through D1 as a res > read more

USB Controlled DMX Interface Kit

Published on 2011-02-14 16:15:56

At this point some of you may be wondering… “um, what is a DMX interface?” While it’s not something you would find in a typical home, it’s widely used in stage and music productions. DMX is short for an EIA-485 based com > read more

Circuit Board Tester

Published on 2011-02-14 08:48:54

Indicates the basic integrity of a printed board Self-powered – 3 to 30V range This little circuit indicates the basic integrity of a printed board, detecting 0V, positive supply voltage from less than 3V to 30V and floating parts. If the probe > read more

Quick On-Board Junction Tester Circuit Diagram

Published on 2011-02-14 07:24:14

Acoustic check of transistor and diode junctions, Also suitable as continuity tester Short circuits or broken pcb tracks can be easily recognized by means of a Multimeter, but this tool can give wrong results when testing the efficiency of a transist > read more

Solar Lamp Using PR4403

Published on 2011-02-14 05:05:16

The PR4403 is an enhanced cousin of the PR4402 40mA LED driver. It has an extra input called LS which can be taken low to turn the LED on. This makes it very easy to build an automatic LED lamp using a rechargeable battery and a solar module. The LS > read more

Two-Led Pilot Light

Published on 2011-02-14 02:29:01

220vAC mains operated, Very simple circuitry This circuit is designed on request and can be useful to those whishing to have, say, a red LED illuminated when an appliance is on and a green LED illuminated when the same appliance is off. Any mains ope > read more

Remote controlled appliance switch circuit

Published on 2011-02-14 02:27:58

Here is a versatile remote controlled appliance switch that can ON or OFF any appliance connected to it using a TV remote. IR remote sensor IC TSOP 1738 is used for recieving the signal. Normally when no signal is falling on IC3 the output of it will > read more

Ultraportable Speaker for MP3 Players

Published on 2011-02-14 02:15:04

The compact, portable iM-237 Orbit M speaker system is an ideal way to share your MP3, CD player, music-enabled phone, or laptop tunes anytime, anywhere. Slip it out of your pocket or purse for an instant audio broadcast. Just plug and play–the > read more

Emergency Light and Alarm

Published on 2011-02-13 21:37:01

Powered by two AA NI-CD batteries, Four switchable options This circuit is permanently plugged into a mains socket and NI-CD batteries are trickle-charged. When a power outage occurs, the lamp automatically illuminates. Instead of illuminating a lamp > read more

Philips SBA1700/37 MP3 Portable Speaker

Published on 2011-02-13 21:33:23

Move with your music! Enjoy stereo sound wherever you go on a stylish travel speaker with folding stand. Secure the line-in cable to use as a lanyard for easy portability. Inside, a digital amplifier eliminates mobile-phone interference. Read more > read more

audio wattmeter circuit

Published on 2011-02-13 18:42:43

This is an easy trick to measure the output of an amplifier.Here resistor R2 acts as the load for for the amp and it should be able to withstand twice the maximum power of the amp you are going to measure.The meter scale must be calibrated and with a > read more

Philips in-Ear Headphones Crystal Sound

Published on 2011-02-13 18:42:00

Philips in-Ear Headphones Crystal Sound SHE9620/28 Rose Gold * Philips in-Ear Headphones Crystal Sound SHE9620/28 Rose Gold * Ultra thin diaphragm delivers clarity and detail sounds Angled Acoustic Pipe channels directional and precise sound * Except > read more

9,000-BTU Portable Air Conditioner

Published on 2011-02-13 18:40:21

Newest addition to SPT’s Portable AC family Dual Hose System with Self Evaporating Technology. This 9,000btu, 3 in 1 system provides multi-season comfort. Designed to efficiently cool, dehumidify any space without permanent installation. Effect > read more

Magnetic proximity switch using CD4013-NE555

Published on 2011-02-13 06:13:54

Here is the circuit diagram of a magnetic proximity switch that finds a lot of applications in many fields.The circuit is based on a magnetic reed switch(S1) as the proximity sensor. A monostable multivibrator based on NE555 (IC1) and a toggle flip f > read more

Dew sensitive switch with opto-coupler

Published on 2011-02-13 04:51:46

Here is a simple circuit that can be used to switch ON or OFF a device when the dew present in the surrounding atmosphere crosses a set value.The circuit uses a dew sensitive resistive element and a comparator based on LM 358 to perform the above sai > read more

Flashing Eyes by BC557

Published on 2011-02-13 00:54:08

Two-LED-eyes follow the rhythm of music or speech, 3V Battery-operated device suitable for pins or badges This circuit was purposely designed as a funny Halloween gadget. It should be placed to the rear of a badge or pin bearing a typical Halloween c > read more

Red Crystal Heart USB Drive 2GB

Published on 2011-02-13 00:12:35

2GB USB Drive with beautiful red crystal heart on keychain. Two halves have a magnetic clasp for additional security. Perfect gift for Valentine’s Day Read more > read more

Dark Activated Led or Lamp Flasher

Published on 2011-02-12 21:30:55

Simple photo-sensitive circuit, 3V battery supply This circuit adopts the rather unusual Bowes/White emitter coupled multivibrator circuit. The oscillation frequency is about 1Hz and is set by C1 value. The LED starts flashing when the photo resistor > read more

Beautiful 5 Arc Satin Nickel Finish Floor Lamp Nice Valentine’s Day Gift

Published on 2011-02-12 21:29:40

These lamps are unique and fun!It’s Classical Design is perfact for any Living Room.It is space saving and is perfect to place at corners or against the wall. Make this item today apart of your home decor furniture or get it as a gift for someo > read more

Simplest lamp flasher circuit with relay

Published on 2011-02-12 21:27:44

This is a very simple lamp flasher circuit that uses only three components (a capacitor, relay and one resistor) other than the lamp. The working of the circuit is very straight forward. When the power is switched ON the capacitor C1 charges through > read more

Street light circuit

Published on 2011-02-12 11:28:25

The circuit diagram present here is that of a street light that automatically switches ON when the night falls and turns OFF when the sun rises.In fact you can this circuit for implementing any type of automatic night light. The circuit uses an LDR t > read more

Oregon Scientific RM313PNA Self-Setting Projection Clock

Published on 2011-02-12 11:23:22

From technology leader Oregon Scientific, this versatile clock shines the time on the bedroom wall with its projection function. The radio-controlled clock regularly resets to the US atomic clock in Boulder, CO for the utmost precision and adapts aut > read more

Remote toggle switch circuit

Published on 2011-02-12 08:49:58

In application level this circuit is similar to that of the circuit given previously. The only difference is in the approach. This circuit is designed by using another method. Using this circuit you can toggle any electrical appliance between ON and > read more

Courtesy Light by 7555 or TS555CN

Published on 2011-02-12 08:46:32

15 seconds delayed switch-off, A good idea for bedroom lamps This circuit is intended to let the user turn off a lamp by means of a switch placed far from bed, allowing him enough time to lie down before the lamp really switches off. Obviously, users > read more

Dark Activated Terrace Lamp

Published on 2011-02-12 00:06:56

Compact circuit, Can be wired in parallel to existing switches This device allows one or more lamps to illuminate at sunset and turn off at dawn.Q1 and Q2 form a trigger device for the SCR, providing short pulses at 100Hz frequency. Pulse duration is > read more

Hall Effect switch

Published on 2011-02-11 23:07:30

The circuit diagram shown here is of a Hall Effect switch. Hall Effect sensor IC DN6848 from Panasonic is the heart of the circuit. The DN6848 has a built-in Hall Effect sensor, Schmitt trigger circuit, power supply regulator and temperature compensa > read more

Neon Light With USB Port Plug – Double Hearts Love Themed

Published on 2011-02-11 21:41:10

This neon light is fun. You just plug it in your port on your computer. I got one for myself and my daughter and she also loves it. Gives out lots of light. It is made well and not expensive. Thanks Amazon. Read More > read more

Set of 100 Pink Mini Christmas Lights – White Wire

Published on 2011-02-11 21:36:06

These lights are made to commercial specifications If one light goes out the rest will stay lit Lights are equipped with Lamp Lock feature, which makes them replaceable, interchangeable and keeps them from falling out. Replaceable bulb, fuses, and bl > read more

Kikkerland Window-Mount Solar-Powered Heart Rainbow Maker

Published on 2011-02-11 21:29:42

This item will indeed throw lights and prisms all over your house. It must be placed in direct, strong sunlight to move, but it will throw static lights in weaker sunlight. If you have a retarded cat that chases after lights, this will provide the li > read more

BLUE 5LED NEON MOTORCYCLE-CAR-BOAT-HOME-POD-LIGHT-BRIGHT 5 LED ACCENT GLOW

Published on 2011-02-11 21:17:43

This DIY 5 LED spreader comes with 5 bright LED bulbs mounted in a 16mm X 10mm X 65mm enclosure. The two outer set leds are at a 45 degree angle, the two mid set are a 60 degree, and the center led is 90 degree. They come with 3 foot long, 22 gauge a > read more

ST6U StripBoard-6U, Accepts DIN Conn.s, 1 Sided PCB, 6.30 x 9.19 in

Published on 2011-02-11 21:09:28

ST6U StripBoard is a prototyping circuit board with a standard stripboard pattern, with tracks running the length of the board. It has 0.1″ hole spacing for DIP integrated circuits and headers and other parts.ST6U is a standard double height (6 > read more

led light running arrows showing the position

Published on 2011-02-11 09:51:32

This is a led light running circuit with a number generated from IC CD4093, CD4520 and CD4094.This circuit can adjust the speed with resistors R1.When entering the power supply to the circuit IC1. A nand gate IC Oscillator generator circuit is connec > read more

Aircraft warning light circuit

Published on 2011-02-11 07:42:04

Here is low cost circuit that can be used for implementing a warning light on the top of tall structures as a warning for low flying aircrafts.Usually such lights are just stay glow type .Here our light is a flashing type, and surely this will draw m > read more

Lamp pulser circuit with LM358-BC337

Published on 2011-02-11 05:23:34

Here is a simple circuit that can be used to pulse an LED or a low power filament lamp. The effect is such that the LED lights up from OFF state gradually and then dims gradually. Such a circuit is very useful in decoration purposes. The circuit is n > read more

Cables Unlimited USB 2.0 to Serial DB9 Adapter

Published on 2011-02-11 01:22:46

This adapter is the easiest way to add a serial port to your computer. Many PDAs, digital cameras, GPS units, barcode scanners, and other equipment require a serial connection and many newer computers don’t have serial ports. This fully plug an > read more

StripBoard-3U Uncut Strips 1 Sided PCB

Published on 2011-02-11 01:19:55

ST3U StripBoard is a prototyping circuit board with a standard stripboard pattern, with tracks running the length of the board. It has 0.1″ hole spacing for DIP integrated circuits and headers and other parts.It has higher quality than traditio > read more

Digital Oscilloscope-40MHz

Published on 2011-02-11 01:05:45

It ‘s different models of portable scopes, meters, and scope/meters. Weve also seen the price tag! Unless you were a field tech with a good sized test equipment budget, they were out of the question. These Personal Scopes have changed all that, > read more

50 Watt MOSFET amplifier using IRF530-IRF9530

Published on 2011-02-09 03:13:00

The first stage of the amplifier is a differential amplifier based on transistors Q1 and Q2. Capacitor C8 is the input DC decoupler, R1 limits input current and capacitor C1 bypasses unwanted high frequencies. The second stage is the driver stage con > read more

Audio Distortion Meter

Published on 2011-02-09 01:35:09

Here is a simple 1KHz audio distortion meter that can measure the Total Harmonic Distortion (THD) on any load at any out put power.Here you have the option to select 2,4,8 or 16 Ohm loads. The circuit works by filtering the 1 kHz fundamental signal u > read more

Dual Tone Train Horn Circuit

Published on 2011-02-08 04:17:55

A dual tone train horn simulator circuit can be made using two NE 555 timers connected in cascade.Here istead of using two NE 555 timers a single NE 556 timer is used which is a nothing but two 555?s in one package and each timers work independently. > read more

Simple audio level meter circuit

Published on 2011-02-07 06:28:37

A simple and low cost audio level meter circuit that can be used to measure the audio level of your sound source.This circuit is a valuable tool for those who are interested in audio circuits. The circuit is designed with a flat frequency response in > read more

Simple Field strength meter

Published on 2011-02-07 02:46:13

Here is a handy field strength meter that can be used to check the strength of AM radio signals.The circuit is a very useful for those who assemble radio transmitters(especially in the tuning of the final stage for maximum range). The circuit is esse > read more

Simulate the traffic light circuit

Published on 2011-02-05 11:12:00

You would never suspect. Traffic jam at the intersection. He do? Has opened the green light and red light. Or to have people turn off. To resolve the question, we try to create this same circuit. Operation of the circuit is IC1 (NE555) is the origin > read more

Micro ampere meter circuit using uA741

Published on 2011-02-04 21:48:16

The micro ampere meter shown here is basically a DC millivolt meter.The circuit gives full scale deflection for 0.1V input.The current to be measured is passed through a known resistance R and the voltage drop across it is measured.Here the IC 1 uA 7 > read more

Led light based music stereo with multi system

Published on 2011-02-03 19:14:35

This circuit is another name for the VU meter. which often have a lot of equipment. Cause problems for people who start training. But this cycle is not much equipment. You can also choose, in the. Running a bar or run with a point. Operation of the c > read more

Signal tracer circuit

Published on 2011-02-03 00:08:07

A high gain amplifier circuit that can be operated from a battery pack of 6 or 9 volt battery pack is shown here.The IC1 uA 741 is wired as a high gain non-inverting amplifier and its output is amplified by a pair of complementary transistors (Q1 � > read more

Temperature controlled DC fan by BD140

Published on 2011-02-02 00:41:34

Here is a simple circuit based on two transistors that can be used to control the speed of a 12 V DC fan depending on the temperature.A thermistor (R1) is used to sense the temperature. When the temperature increases the base current of Q1 (BC 547) i > read more

Guitar pre-amplifier using uA 741

Published on 2011-02-01 21:33:39

A preamplifier circuit suitable for high impedance type electric guitar pickups is given here.The circuit is based on a uA 741 op-amp (IC1).The IC1 is wired as a non-inverting amplifier.The POT R1 can be used as a volume controller.The POT R6 can be > read more

TDA4935 bridge amplifier

Published on 2011-01-29 07:52:59

TDA4935 is 2x15W high quality audio amplifier IC from Siemens. The IC can be used in stereo mode or bridge mode. In stereo mode it can deliver 15W per channel and in bridge mode it can deliver 30W into a 8 ohm load at 30V supply. TDA4935 requires ver > read more

Tap tempo circuit using ic cd4011

Published on 2011-01-27 23:38:39

This circuit will have an effect than Tap the rhythm circuit other because the whistle is giddy, which vividly than usual knock. You can also adjust the speed with 10-40 strokes per minute. Operation of the circuit, we will be divided into three main > read more

Ringing phone light flasher

Published on 2011-01-27 03:25:53

This circuit can be used to glow a bulb or turn a alarm when the phone rings.Using this circuit nuissence of telephone ring at night can be avoided. When the telephone rings the line voltage rises to 72 volts.At this time the LED in the opto-coupler > read more

Telephone operated DTMF remote by KT3170

Published on 2011-01-26 08:35:43

The circuit given below is of a telephone operated DTMF remote. The circuit can be used to switch up to 9 devices using the keys 0 to 9 of the telephone. Digit 0 is used to switch the telephone system between remote switching mode and normal conversa > read more

Music box automatically with IC UM66T

Published on 2011-01-23 09:20:00

This is an integrated music box Self Promotion Nat, when I open the music box to hear the music out. You can choose music in several voices, just change the IC number only. Operation of the circuit is when the power supply and switch S1. The IC IC1 i > read more

Multi level power supply with 78xx series

Published on 2011-01-19 10:23:35

This is an electrical circuit to supply DC power positive and negative. It also has multiple power levels as well. The equipment it easy to buy and affordable. Operation of this circuit, when T1 was to convert the AC voltage from 220 volts down to 15 > read more

Class A audio amplifier 5W using IC-NE5532

Published on 2011-01-17 10:49:54

Among the final amplifier we called. Regional Power Amp, will it work on several well-known as Class A, Class B, Class AB etc. Each class of the above, to honor the Class A was superior to the sound quality. best. However, class A power output to a l > read more

usb light for notebook

Published on 2011-01-11 08:23:17

When more work constantly. Son and uncomfortable, symptoms need to sleep watching the ball. I tend to use the laptop in the bedroom with him, but it will turn the lights in the room will interfere with his son, not that close to sleep. So I thought a > read more

Random number with led 1 digit

Published on 2011-01-07 10:52:47

This is a circuit diagram showing the random nature of LED 7 segment. In the diagram circuit IC1 – LM555, R1, R2 and C2 on the circuit a sensitive multi-Stable Brett Foster (Astable. multivibrator circuit) function generator signal square (Squa > read more

Reducing Relay Power Consumption

Published on 2011-01-06 00:44:09

Relays are often used as electrically controlled switches. Unlike transistors, their switch contacts are electrically isolated from the control input. On the other hand, the power dissipation in a relay coil may be unattractive for battery-operated a > read more

Handy Time Delay With Relay Output

Published on 2011-01-04 02:42:39

This circuit is designed to provide delayed relay switching action at power on. The delay is a function of the time constant produced by the combination of R1 and C1. At power on, C1 charges slowly via R1 and the coil of the relay. When the voltage a > read more

Momentary Switch Teamed With Latching Relay

Published on 2011-01-01 20:38:37

This circuit allows an SPST momentary pushbutton to act as a push-on push-off switch, using a DPDT latching (bi-stable) relay. It was originally intended to allow a single pushbutton switch on the dash of a vintage car to provide a latched function. > read more

Audio Amplifier Output Relay Delay

Published on 2010-12-31 09:14:57

This is a simple circuit which I built to one of my audio amplifier projects to control the speaker output relay. The purpose of this circuit is to control the relay which turns on the speaker output relay in the audio amplifier. The idea of the circ > read more