Electrical4U 
Electrical engineering books serve different learning goals. An introductory electronics guide, a university power-systems text and a professional handbook are not interchangeable. Choose a book by the subject you need, its assumed mathematics, the balance of theory and worked examples and the edition required by your course or work. Before buying, compare the contents and … Read more
What is Transmittance? Transmittance is the ratio of radiant flux transmitted through a material or object to the incident radiant flux under specified spectral and geometric conditions. Incident radiation can be transmitted, reflected or absorbed. Transmission and reflectance can be regular or diffuse because of scattering. For the same beam area and measurement geometry, transmittance … Read more
What is a PNP Transistor A PNP bipolar junction transistor has a thin N-type semiconductor base between emitter and collector regions made from P-type semiconductors. Its three terminals are emitter, base and collector. The PNP transistor contains the two junctions described in the linked PN junctions diodes overview, but two separate back-to-back diodes cannot reproduce … Read more
What is a NPN Transistor An NPN bipolar junction transistor has a thin P-type semiconductor base between emitter and collector regions made from N-type semiconductors. Its three terminals are emitter, base and collector. The NPN transistor contains two PN junctions diodes, but two separate back-to-back diodes cannot reproduce transistor action because they do not share … Read more
What is a Band Pass Filter? A band pass filter, also called a BPF, passes a selected range of frequencies while attenuating frequencies below and above that range. Real filters have finite attenuation, insertion loss and transition regions rather than perfect pass and stop bands. A low pass filter passes frequencies below its cutoff and … Read more
What Are Harmonics? Harmonics are sinusoidal components whose frequencies are integer multiples of a fundamental frequency. In power-quality work, harmonic components combine with the fundamental to produce a non-sinusoidal voltage or current waveform. They are often unwanted, but harmonic generation and measurement are also used deliberately in signal processing and RF systems. A harmonic often … Read more
An electrical filter changes a signal according to frequency. It passes some frequency components with relatively little loss and attenuates others. The transition is gradual in every realizable filter. Analog filters can use resistors, inductors, capacitors and amplifiers. Their component values and topology set the gain and phase response as a function of frequency. A … Read more
Portable backup products fall into two different groups: battery power stations and fuel-burning generators. A useful choice must have enough continuous and surge power for the intended loads, suitable outlets, a practical energy or fuel capacity, and clear safety instructions. The right specification depends on the job. Add the running watts of the equipment you … Read more
An Arduino starter kit can give a beginner one place to learn basic circuits, microcontroller programming and safe prototyping. Useful kits pair a documented board with clear lessons and labelled parts such as LEDs, sensors, buttons and buzzers. The parts should match the projects, and the learning material should be available in a format your … Read more
What is a Klystron Tube? A Klystron, also called a Klystron Tube or Klystron Amplifier, is a linear-beam vacuum tube that uses an electron beam and resonant cavities to generate or amplify radio-frequency power. Russell and Sigurd Varian developed the first successful klystron at Stanford in 1937, with important contributions from William Hansen and other … Read more