Triode Working Principle

A triode is an electron tube that consists of three electrodes, an anode plate, a cathode filament, and a control grid. A triode is usually used as an amplifier for audio signals, in electrical circuits, and as an oscillator.

Small glass triodes are mainly used as audio amplifiers while the large triodes are used as radio transmitters for radio frequency.

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This segment will highlight the operation and explain the working principle of the triode.

The first process in the working of a triode is called thermionic emission. In this process, heat is applied to the metal cathode to release electrons into the tube.

A separate current flowing through the filament heats the cathode red hot. The filament is a thin metal that conducts electricity. In powerful triodes that generate radio frequency, the cathode is usually the filament itself. However, in most triodes, the filament is separate and heats the cathode electrode.

The air in the tube is removed virtually through electron transfer. This allows the electrons to move freely within the tube.

A positive DC voltage is applied to the anode. The voltage ranges from 20V to thousands. Once the anode is positively charged, the negative electrons are attracted to the anode. A flow of electrons from the cathode to anode is created as the positive and negative electrons attract.

How is the magnitude of currents controlled?

To control the magnitude of currents flowing between the cathode and anode, an appropriate voltage is applied between the grid and the cathode. The grid is the electrons’ gate. If the grid is more negative, it repels some electrons to reduce the current since fewer will get through the anode. A more positive grid attracts more electrons and increases the current since more electrons will get to the anode.


Amplification is a resulting process where a low power varying signal control a much powerful anode current.

If there is variation in the grid voltage, it will result in proportional variations in the anode current.

Voltage gain

This is the result of the placement of appropriate load resistance in the anode circuit to cause the voltage across the resistance to vary and it could be larger than the input voltage variations.

In operation, the triode is similar to the n-channel JFET. However, the difference is that the triode’s anode current depends on the anode voltage and grid voltage.

This is the basic working principle of the triode.

Arduino Uno Introduction

If you are an electronic enthusiast, you have probably heard of Arduino Uno. If you haven’t heard of it and you enjoy building electronics projects, then you are in the right place. Here, we will discuss what Arduino Uno is and why you should consider it for your electronics projects.

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What is Arduino Uno?

Arduino is an open-source platform for building electronics projects. It consists of both physical and software boards. It is more popular with people who are not experienced with technology as it is an easy-to-use platform that allows users to read inputs and turn into outputs. An example of input is light on a sensor while its output may be activating a motor.

Over the years, Arduino has gained popularity and has been used in thousands of projects ranging from basic to complex electronics projects.

Why Do People Prefer Arduino?

  • Simple and accessible

The simplicity of this platform is one of the top reasons why thousands of projects have been developed on it. Beginners are particularly happy with this platform as it offers an easy way to develop projects and applications. Advanced users are also excited about the flexibility of the platform.

  • Cross-platform

Another thing that you need to know about Arduino Uno is that it runs on Windows, Linux, and Macintosh OSX operating systems. Unlike other microcontrollers that are limited to Windows, Arduino allows users to develop electronic projects using different operating systems.

  • Open source and extensible software

Experienced can use the Arduino software, which is published as open-source tools. Users can expand the language through C++ libraries. If you want to understand the technical details, you can use the AVR C programming language.

  • Open source and extensible hardware

Both beginners and experienced circuit designers can use the plans of the Arduino boards, which are hosted under a Creative Commons license. This means that users can extend and improve it to fit their specific needs. Beginners have the option of building a breadboard version of the module to help them understand how it works.

  • Inexpensive

Compared to other microcontrollers, Arduino boards are inexpensive. For less than $50, you can get pre-assembled Arduino modules.

These are the features that define Arduino Uno. Clearly, you can see that both beginners and experienced circuit developers can use this open-source platform to start or develop their projects or applications. The good thing about it is that it is inexpensive and you can always try out with a low investment.

Basic information of Transistor D882

A transistor is a device that manages the flow of electrical power and electronic signals to a circuit. It has the ability to amplify and switch the electronic signal to help the electronic circuit perform a certain action for an electronic device.

The Transistor D882 is a common type of transistor found in many electrical applications. It is most commonly used in battery charger circuits, voltage regulator circuits, power supply circuits, amplify audio signals, and driving motors. For instance, audio amplifier equipment uses the transistor D882 the most. Everything from the bell circuits to the receiver circuits utilizes this transistor.

Here are the technical specifications of Transistor D882:

  • Max Collector-Emitter Voltage: 30V
  • Max Collector-Base Voltage: 40V
  • Max Collector Current: 3A
  • Max Emitter-Base Voltage: 5V
  • Max Collector Dissipation: 10 Watts
  • Max Transition Frequency: 90 MHz
  • Minimum DC Current Gain: 60
  • Maximum DC Current Gain: 400

You could make an entire audio amplifier device from this one transistor. Just note its max collector current is 3A, which means all the switching loads must be less than 3A. It will ensure you stay safe as you operate the amplifier. But there needs to be a good base resistor too. And if you’re operating the transistor in an environment under -55°C or higher than 150°C, then your transistor will be ruined.

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If you’re working on an electronic project as a hobbyist or for educational or commercial purposes, then you’ll get plenty of use out of a transistor D882. Unless you have experience as an electrician, it is a good idea to read a professionally written guidebook or tutorial on how to replace or install a transistor D882. It might be a small electronic device, but it is very powerful. Any mismanagement or miscalculation along the way could make your electronic device or circuits unsafe.

Basic Information of Transistor C1815

The transistor C1815 is used in a number of different educational and commercial electronic projects. Anytime audio frequency amplification is desired, the transistor C1815 will probably be used in the electronic device. Its collector-base voltage is 50 volts, so any circuit with under 50 volts can use the transistor.

Here are the technical specifications of transistor C1815:

  • Max Collector-Emitter Voltage: 50V
  • Max Collector-Base Voltage: 60V
  • Max Collector Current: 150mA
  • Max Emitter-Base Voltage: 5V
  • Max Collector Dissipation: 400 mW
  • Max Transition Frequency: 80 MHz
  • Minimum DC Current Gain: 70
  • Maximum DC Current Gain: 700

There are different audio amplification stages in which the C1815 transistor can be utilized. It can be used as a small audio amplifier, preamplifier, and as a switch for electronic circuits. The C1815 transistor has the ability to drive relays for low power LED lighting, high powered transistors, and any other component of an electronic circuit.

Suppose you need to replace the C1815 transistor in an electronic device or replace another transistor with the C1815 transistor. In that case, you need to know which transistors are the equivalent of a C1815 transistor in terms of specifications. Here are some of the equivalent transistors:

  • C945
  • C3920
  • C3916
  • C3922
  • C3921
  • C3919
  • C3917

However, these other transistors could have a different pin configuration. If you purchase an equivalent transistor, it must have the same pin configuration as the C1815 transistor. If you are not sure about which replacement is acceptable, then have an electrician help you out. BC557 is the PNP transistor of the C1815 model.

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Overall, the applications for the transistor C1815 include preamplifier circuits, Class A amplifiers, Class B amplifiers, Push/Pull configuration circuits, and all types of switching actions in electronic devices. Virtually all audio amplification devices must perform these electrical actions.

Basic Information of IC 7404

The IC 7404 is a hex inverter chip with a huge operating voltage range and wide operating conditions. It features six different inverter gates, and there are an input and an output for each gate. When an input signal is transmitted to one of the gates, it becomes inverted when it leaves through the corresponding output gate.

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For instance, if the input signal is low as it goes into the input gate, then it will come out as a high output signal from the output gate. The opposite is true, as well. If the input signal is high, the output signal is low. That is the purpose of an inverter chip, but especially the IC 7404.

There are 14 pins found on the IC 7404 chip. You’ll see most of the pins make up various input gates and output gates. Only two pins are not input or output gates: the positive supply pin and the ground pin.

Take a look at the gates below:

  • Pin 1 – A Input Gate 1
  • Pin 2 – Y Output Gate 1
  • Pin 3 – A Input Gate 2
  • Pin 4 – Y Output Gate 2
  • Pin 5 – A Input Gate 3
  • Pin 6 – Y Output Gate 3
  • Pin 7 – Ground
  • Pin 8, – Y Output Gate 4
  • Pin 9 – A Input Gate 4
  • Pin 10 – Y Output Gate 5
  • Pin 11 – A Input Gate 5
  • Pin 12 – Y Output Gate 6
  • Pin 13 – A Input Gate 6
  • Pin 14 – Positive Supply

All digital electronics have an inverter chip in them. The IC 7404 is constructed with either a PMOS transistor and a resistor or just an NMOS transistor. The output gates interface to TTL, CMOS, and NMOS.

Only an experienced electrician should replace an IC 7404 chip. It costs between $1 to $2 at a typical electrical parts store.

Non Polarized Capacitor Types

A capacitor is an electronic component with two terminals that store electricity temporarily. There are two types of capacitors: non-polarized and polarized. Non-polarized capacitors have no negative polarity or positive polarity, while polarized capacitors have a positive pole and negative pole.

There is only one type of polarized capacitor, which is the electrolytic capacitor. The non-polarized capacitors are more popular because they are inexpensive and have better longevity. It also doesn’t matter which direction they’re installed either.

However, the type of non-polarized capacitor does matter. There are at least eight different types of non-polarized capacitors. Let’s briefly examine them below.

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Ceramic Capacitors

Ceramic capacitors are used the most because they’re the cheapest and the most tested capacitors. They have been around since the 1930s but have seen improvements over the many decades. Ceramic capacitors are used a lot in radio frequency circuits.

Silver Mica Capacitors

You won’t see silver mica capacitors used too often because they cost more than most other capacitors. But they are highly durable capacitors because of their stability and temperature resistance. Circuits that depend on stability, such as filter circuits and oscillator circuits, will use silver mica capacitors.

Polyester Capacitors

These are cheaper capacitors with good accuracy and less prone to leakage. Unfortunately, their stability is not as good as other capacitor types.

Polystyrene Capacitors

You can get a lot of accuracy out of polystyrene capacitors. They’re difficult to find on the market, though. Most circuit designs don’t use them anymore. Besides, they were pretty expensive, to begin with.

Polycarbonate Capacitors

Polycarbonate capacitors are also kind of pricey, but they’re made from high-quality material and last a long time. They can withstand high temperatures without leaking.

Polypropylene Capacitors

Polypropylene capacitors are high performing capacitors with great stability but a tad expensive.

Teflon Capacitors

No other capacitor is more stable than a Teflon capacitor. It is one of the most accurate capacitors with virtually no leakage whatsoever.

Glass Capacitors

Glass capacitors may be the most expensive of all capacitors, but they’re extremely tough and stable.

IC 7474 Pin Diagram and its Application

The IC 7474 is an electrical chip consisting of dual D-type positive edge-triggered flip flops. Their outputs include preset and clear. Flip flops are often seen in electronic and computer devices because they have the ability to store data. Each flip-flop can store approximately one bit of data. There are many types of flip-flops, but the “D-type” indicates it is for storing data.

Diagram and Application

There are 14 pins associated with the IC 7474 chip. Each pin has a specific purpose in making an electrical circuit function. The pins are as follows:

Pin 1 – Clear 1 Input

Pin 2 – D1 input

Pin 3 – Clock 1 Input

Pin 4 – Preset 1 Input

Pin 5 – Q1 output

Pin 6 – Complement Q1 output

Pin 7 – Ground

Pin 8 – Complement Q2 output

Pin 9 – Q2 output

Pin 10 – Preset 2 Input

Pin 11 – Clock 2 Input

Pin 12 – D2 input

Pin 13 – Clear 2 Input

Pin 14 – Positive Supply

The D input is like a memory cell, delay line, or zero-order hold. When D input information is triggered to go to the flip flops, the triggering has nothing to do with the transition of time. It has more to do with the level of voltage.

However, the D input information can be altered whether the clock is set to high or low. This won’t affect any of the outputs if there are no violations of the hold times and data setup. On the other hand, if the clear inputs or preset inputs have a low logic level, the outputs will be reset no matter the logic levels of the clock inputs.

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Overall, the IC 7474 has wide operating conditions because of its large voltage range operation. If you were to purchase the IC 7474 chip separately, it would only cost you a few dollars. But you must have experience working with electrical components if you’re going to install or replace this chip. That way, you can stay safe.

Basic Information of 74LS138 3 to 8 Line Decoder IC

74LS138 3 to 8 Line Decoder IC utilizes the silicon-gate TTL technology. The design of the chip is for de-multiplexing or decoding applications. The 74LS138 comes with three inputs to eight output setup. It also has a special design that allows it to be used in data-routing applications or high-performance memory-decoding. It is effective in applications that require short propagation delay times.

The decoders have a special function of minimizing the effects of system decoding in high-performance memory systems.

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74LS138 3 to 8 Line Decoder IC Configuration

The basic configuration of the 74LS138 3 to 8 Line Decoder IC is that it has 3 inputs to 8 outputs setup. Each pin in the decoder has a special function that differentiates it from the rest.

A, B, C: these are address input pins

G2A (Enable input – active LOW), G2B (Enable input – active LOW), G1(Enable input – active HIGH)

GND – Ground

Y0, Y1, Y2, Y3, Y4, Y5, Y6, Y7: Out pins

Users can pick different available packages of this device.

Features of 74LS138 3 to 8 Line Decoder IC

The dominating features of the 74LS138 include the following:

  • It has been designed for high-speed performance
  • It simplifies cascading with the incorporation of the three enable pins
  • It has de-multiplexing capabilities
  • It delivers high performance
  • At has an ESD protection
  • It has balanced propagation delays
  • Its inputs can accept voltages that are higher than VCC
  • A typical propagation delay is 21nS
  • Another great feature is that it is consumption-friendly when it comes to power. It does not consume a lot of power, thus, help in reducing the cost of power. Its typical consumption is 32mW
  • It can operate within a wide range of temperatures i.e. from -40 degrees Celsius to +125 degrees Celsius.

An overview of 74LS138 3 to 8 Line Decoder IC

The chip has been designed for high-performance us in memory-decoding or data-routing applications that need short propagation delay times.

In most applications, any delays are not tolerated because the performance is determined by the memory unit data exchange rate. Using the 74LS138 3 line decoder is ideal in such applications because the delay times are permissible using this decoder.


You can use it for:

  • Servers
  • Line decoders
  • Digital systems
  • Line de-multiplexing
  • Memory circuits
  • Telecom circuits.


SCT3xxxxR SiC MOSFET Overview

ROHM made the announcement of the availability of a new trench gate structure, SiC MOSFETs. This is a six-SCT3xxx xR series, which has a 4-pin package to maximize the performance of switching, reduce power consumption, reduce switching loss. Compared to the 3-pin package, this 4-pin package enhances efficiency greatly. The 3-pin package does not separate the driver and power sources as the 4-pin package does. This helps reducing parasitic inductance components, which eventually helps in maximizing the switching speed of SiC MOSFETs.

What is SiC MOSFETs ideal for?

Well, SiC MOSFETs are ideal for solar inverters, server power supplies, and charging stations for electrical vehicles.

The reason why SCT3xxxxR SiC MOSFET is ideal for these high-demanding electrical installations is that they require high efficiency, which is offered by the 4-pin package that maximizes the switching speeds.

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Features of the SCT3xxxxR SiC MOSFET

  • Reduces switching loss by about 35%

One of the most amazing features of SCT3xxxxR SiC MOSFET is that it reduces switching loss by about 35%. Thanks to the 4-pin package that reduces the effect of the inductance component, the driver source and the terminal source are separated to reduce switching loss. Users simply need to add the turn-off and turn-on loss to reduce switching loss by about 35% compared to conventional products.

  • Fast switching speed and reverse recovery

Another outstanding feature of SCT3xxxxR SiC MOSFET is the speed at which it operates. Whether you are switching on or reserving, the speeds are extremely fast.

  • High speed and low on-resistance

The SCT3xxxxR SiC MOSFET works excellently with silicon devices. The electrical characteristics of ROHM’s SiC MOSFET allow it to work well even at high temperatures. This means that there are high speeds recorded and low on-resistance because the peripheral components are downsized.

  • Flexible operating temperatures

SCT3xxxxR SiC MOSFET can operate with temperature ranging between -55 degrees Celsius to 175 degrees Celsius.  This wide range of temperatures allows it to operate high-demanding devices while maintaining high efficiency.

  • Evaluation board

The evaluation board of SCT3xxxxR SiC MOSFET is effective as it can evaluate other ROHM SiC MOSFETs. The features of the evaluation board are excellent and allow for adjustments depending on the electrical requirements. It also has in-built protection and an overcurrent protection function.

These are the main features of the SCT3xxxxR SiC MOSFET. Of course, it is a revolutionary tech improvement that enhances efficiency while reducing power consumption.

How to Test 78L05 Voltage Regulator

A voltage regulator is a component that maintains a fixed amount of output voltage regardless of the input voltage. You can find voltage regulators in the power supplies of computers and other electronic devices. Whenever DC voltage stabilization is required, a voltage regulator is likely going to be used to perform that action.

The 78L05 voltage regulator is one specific type of voltage regulator. The “78” number identifies it as a positive voltage regulator, while the “05” signifies the output voltage is 5 volts. It is a three-terminal voltage regulator, which includes the input terminal, ground terminal, and output terminal.


A voltage regulator test will determine the amount of voltage going into the voltage regulator and the amount of voltage going out of the regulator (input and output). You will need a multimeter to conduct a measurement of the input voltage and output voltage. It is an electronic measuring instrument designed to measure resistance, voltage, and current.

When you’re ready to perform the test, you can start by testing the input voltage. Switch the setting on the multimeter to “DC voltage.” It should have a “V” symbol or something similar. You’ll see the multimeter has a positive probe and a negative probe. Attach the positive probe to the input pin on the bottom of the voltage regulator. Then attach its negative probe to the ground pin.

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The multimeter has a digital screen that will indicate the amount of voltage. The input voltage should be higher than the output voltage by about 1 to 2 volts. You can find out by performing a similar measurement of the output voltage. All you need to do is take the positive probe off the input pin and place it on the output pin. You can leave the negative probe on the ground pin.

The amount of output voltage indicated should be 5 volts because of the “05” associated with 78L05. If you see a different number other than 5, then your voltage regulator is defective.