1.  It is not possible for all the electronic beginners to buy a device which can test all the components as it is highly costly.2.  So for all those peoples “All in one Tester” is a solution.3.  This circuit is quite easy to make and also cost fewer amounts to their pockets.4.  This device can test approximately all the components starting from simple resistors till typical IC’s.5.  With the help of this device it is also easy to check the polarity of components, continuity testing and logic state as      well as multivibrator activity.

This is a very easy circuit . This can be employed in automobiles as a sequential indicate light. This circuit is constructed with the help of two ICs first one is a CMOS timer IC i.e. 555 timer and another one is the decade counter IC i.e. CD4017. In this circuit astable mode of the 555 timer IC is been used to trigger the counter. Also few other discrete components are used in the circuit. 

 Op-amp 741 is a very well-known as well as very usable IC in many of the projects like amplifier circuits, voltage follower circuits, current to voltage changer or voltage to current changer and many more other applications. So for the proper working circuit it is highly necessary that your op-amp works correctly. So here the circuit that will help you to check whether your op-amp is in good condition or it is faulty.

This circuit is too much pocket friendly at the same time simple to build. 555 timer, capacitor, transistors, inductor and few resistors are needed to construct the circuit.When a new call coms this circuit will provide you aoptical effect by flashing of LED. In circuit is so much useful where you are not been able to put your phone in ringing volume viz: in the offices, in your house where your infant or your any people of your family sleeping and you don’t want to disturb them or else you even don’t want to listen your phone ringtone and need some silence in your home. You can also use this circuit in the place which is full of noise and mobile ringtone and you are not been able to hear your mobile ringtones, this circuit is too much useful for you in such situation.

Main component of this circuit is IC NE555 timer.IC1 in this circuit works in astable mode. Other components that are used in this circuit are resistor, capacitor, LEDs and transistor.When power supply is on and switch pressed then voltage at pin2 and pin6 of IC1 drops. At the same duration voltage at pin3 of IC1 gets high and LED glows.For driving big quantity of LEDs (say around 50), a PNP transistor T1 (BD140) linked in the output terminal of the circuit.In this circuit we have used only 9 LEDs. We have divided the 9 LEDs in the group of three LEDs which is attached with 82 ohm resistor.

The project which is demonstrates a very interesting project of E-Toss. E-Toss is a very good option in place of coin toss. This project can also be used as game i.e. it can be played by two or more members and they have to choose whether a head or tale and press the switch. If the result comes out to be same what a player predict then that player won. This circuit can also be used in the games like cricket and many more where there is need to make any decision.

In the circuit when the voltage goes above 2V then at that time large current will pass through the collector of T2. And also the base current of transistor T1 goes up so that it can bring this transistor in the conduction stage. However at T1 transistor creates more and more negative. Exactly same thing occurs with the base of T2. And in turn of this T2 gradually closes and act against the starting growth of current. That how a steading effect achieved and we got a fixed value of current that will flow from LED.Rating of R in the circuit is equivalent with the LED current divided by 0.5

555 timer IC is highly used IC in the projects as it is low in price as well as provide high performance. You can find large number of projects on the internet made up of using 555 timer. Here is another simple project made with the help of 555 timer which can offer you hour of enjoyment.The project is made with the help of NE555 timer along with support of some other discrete components. The project which is shown here is clearly a triggering circuit and with the support of variable resistor VR1 in the project timing is adjusted.

These circuit cost too less to your pocket as it made up of NE555 IC, buzzer , some resistors and capacitors. These circuit is also a user friendly. As with the help of just by one button pressing you will let other that you are in panicking condition without any difficulty.In these project astable mode of IC NE555 is used. Resistor R1 and R2 along with capacitor C2 used in the circuit so to tune the frequency. In the starting the circuit remain in the disable state. Now when the button is pressed the pin 4 and pin 8 of IC1 gets the high voltage. In turn of these the voltage at pin 2 goes down gradually and voltage at pin 3 starts increased in the same manner. And a situation arrives when the sound comes out from the buzzer. 

The circuit which is shown here is too easy circuit. In this circuit IC1 is mounted in a unusual mode. At the time when power resumes, pin 2 of IC1 which is through capacitor C1 is grounded goes low and pin 3 of same IC switches to high. In turn of this pin 4 of IC1 which is a reset pin switches to high state for approximately 10 seconds. When the voltage at C1 reaches to 2/3 of the supplied voltage, capacitor starts discharging and output switches to low, grounding the pin 4 which is a reset pin and hence the fell circuit move out of action.