Engineering and Technology

Here is my youtube video covering details about this project: Here is the Hindi Urdu version of the same circuit build video on my youtube channel: Function: This circuit consists of 38 LEDs to form a butterfly image. Among them, 14 red LEDs form the middle heart, and 24 white LEDs form the two wings of the butterfly. The red heart is always on and the white wings will continuously flash to display flying effect. In the meantime, the buzzer will sound the song of “Happy Birthday to You” Principle: When power on, the two triodes VT2, VT3 will compete to connect. Since there is difference among components, only certain one triode will be connected firstly. If VT3 is firstly connected, then VT3 collector voltage will decrease, LED1-12 and LED27-38 will be on. The right port of the capacitor C2 is close to zero voltage; because the two ports voltage of the capacitor cannot change suddenly, VT2 base will become zero voltage nearly (or negative voltage, if original ...

This post is shared only for educational and learning purpose. This is not sponsored. Here in this above image you can see a soldering iron which is battery operated and it is cordless. You can charge its battery and can take it with you anywhere and perform soldering anywhere without the headache of electricity. There is no risk of electric shock too. Regular soldering iron is a dangerous tool which killed many technicians. The reason is as this tool is very frequently used by technicians and it is in the hand electrified. In this situation if its element is breaking down and is touching to its metal body, and a person is soldering with it; it could kill or serious injury and fatal accident could occur in such a situation. The battery operated cordless soldering iron totally eliminates this risk and is providing nice and clean safe job to a service technician or service engineer. Electronics repair itself is a difficult and cumbersome job. This is a must that a technician or...

Timer circuit testing Here is youtube video English version on this subject: Here is youtube video Hindi/ Urdu version on this subject: The timer circuit which we discussed before in the last post which is here can be tested using power supply and some arrangement. Here in the following lines I will discuss how to test the circuit. This delay automatic on circuit can switch on the power with delay of  a few seconds to a few minutes. The delay time can be adjusted using a potentiometer or changing the timing capacitor if a big duration of the time is required. This circuit is especially made for creating on delay for refrigerators, freezers and air conditioners. As these units are sensitive for ON and OFF. The refrigeration and air conditioner machine should not be switched on immediately after switch off. Instead there must be a delay of a minute to a few minutes say three minutes in most cases between off and on. Otherwise the compressor may da...

Relay   Relay is a very important device or component used in electrical and electronics systems. Relay is used always everywhere. If this is house hold, Automotive, Industry, Locomotive, plane or any other electrical system; relay will be everywhere. Relay have different types and shapes. They are basically electro-mechanical or electromagnetic devices used in all electrical or electronics systems. Relay basically acts like a switch which is electrically controlled. In very simple form a relay it can be single pole single through type. In which there could be a pair of contacts making a normally open or normally closed switch which could be activated by an electromagnetic coil and a spring. How a Relay functions  A relay is working like a switch. The ordinary switch is activated through your finger whereas a relay is activated through electromagnetic coil and is activated electrically. There is one electromagnetic coil in a relay which activates a switch. The coil ...

Here is the Youtube video English version associated to this article: Here is the youtube video Urdu version: What is reverse engineering? Reverse engineering is a term used to dig behind the idea or the concept at which something is build. The reverse engineering reveals the basics of a system on which the system is built. In Electronics the reverse engineering is used to breakdown a build circuit in its basic schematic circuit diagram. This is done to translate the circuit from original system to paper. Once the circuit is got on paper, it is easy then to copy it, circulate it, modify it or enhance it after studying it in detail. The reverse engineering of small circuit is easy to copy it to paper part by part and note down the components values with care. Anyhow sometimes it is very difficult to understand a pre build circuit when there transformers, some complex coils or some custom made components are used in a circuit. Also it becomes more troublesome when d...

Here is my youtube video showing details of such product in video: Here is the Urdu Hindi version of this instrument review on Youtube: You can buy this product on ICStation.com the link is here below: http://www.icstation.com/blue-digital-display-voltmeter-ammeter-power-meter-260v-20a4400w-p-11981.html Product Introduction: 1.Operating Voltage:AC 80-260V 2.Testing Voltage:AC 80-260V 3.Rated Power:20A/4400W 4.Operating Frequency:45-65Hz 5.Measurement Precision:1.0 level 6.Connection Picture: Function: 1.Electric parameter measurement function (voltage,current,active power,electric energy) 2.Operating time function (record load accumulated operating time) 3.Overload alarm function (if it is over power alarm threshold,the backlight will   flash and sound an alarm) 4.Power alarm threshold preset function (users can set power alarm threshold freely) 5.Electricity quantity,operating time key clear function 6.Backlight function ...