induction cooktop

How Induction Cooktops Work

jojo February 3, 2016 1 Comment
Working of induction cooktops Induction cooktops are very popular in all households. They have lots of advantages over gas and electric cooktops and are more efficient. But have you ever wondered how an induction cooktop works? The working of an induction cooktop is very simple. It has more to do with electrical engineering than electronics but this caught my eye because an induction cooktop, a product that has a billion dollar market, uses a very base level technology for...
read more

Basic Controls of a CRO

jojo September 24, 2009 6 Comments
Number of controls are required to be provided on a panel of CRO to facilitate its proper functioning. Intensity control is provided for adjustment of brightness of the spot on the screen. It is accomplished by varying the voltage between the first and second anodes. The horizontal and vertical position controls are provided for moving the beam on any part of the screen. It is accomplished by applying a dc voltage to horizontal or vertical deflection plates. Similarly there...
read more

CRT-Cathode Ray Tube

jojo September 24, 2009 3 Comments
Cathode ray tube essentially consists of an electron gun for producing a stream of electrons, focusing and accelerating anodes for producing a narrow and sharply focused electron beam, horizontal and vertical deflection plates for controlling the beam path and an evacuated glass envelope with phosphorescent screen giving bright spot when struck by a high velocity electron beam. A cutaway view of an early CRT is shown in figure. CRT-Cathode Ray Tube Electron Gun Assembly. The electron gun assembly consists...
read more

CRO – Cathode Ray Oscilloscope – Ultimate Guide

jojo July 20, 2018 28 Comments
A CRO (Cathode Ray Oscilloscope) is an electronic instrument used for studying various electrical & electronic parameters and behaviors. CRO is basically an XY (2 dimensional) plotter which can plot an input signal vs another signal or an input signal vs time. A cathode ray oscilloscope is used to study waveforms, transients, time based or frequency based analysis. Introduction to CRO – Cathode Ray Oscilloscope The cathode ray oscilloscope is an extremely useful and versatile laboratory instrument used for...
read more


jojo September 23, 2009 5 Comments
Q-Meter We know that every inductor coil has a certain amount of resistance and the coil should have lowest possible resistance. The ratio of the inductive reactance to the effective resistance of the coil is called the quality factor   or Q-factor of the coil. So Q = XL / R = ωL / R A high value of Q is always desirable as it means high inductive reactance and low resistance. A low value of Q indicates that the...
read more

Electronic Multimeters

jojo September 23, 2009 2 Comments
Electronic Multimeters It is one of the most versatile general purpose instruments capable of measuring dc and ac voltages as well as current and resistances. The solid-state electronic multimeter (or VOM) generally consists of the following elements. A balanced bridge dc am­plifier and a PMMC meter. An attenuator in input stage to select the proper voltage range. 3. A rectifier for convert­ing of an ac input volt­age to proportionate dc value. 4.  An internal battery and additional circuitry for...
read more


jojo January 18, 2011 No Comments
Electronic Galvanometers A vacuum tube or transistor amplifier, followed by a milli-ammeter may be employed as a detector. Some of such devices have arbitrary scale values, sometimes with variable gain, and are designed simply as balance indicators. The sensitivity may be of the order of a microvolt per scale division or better, and the input impedance is in the range of meg ohms, so the current drawn from the measured source is usually negligible. Such instruments have the advantages of ruggedness...
read more

Balanced Bridge Voltmeters

jojo September 23, 2009 No Comments
Balanced Bridge Voltmeters Such voltmeters can be used for measurement of both dc and ac voltages and are very popular. These voltmeters are available in both versions, vacuum tube type and transistorized type and are described below: (a) Balanced Bridge Triode VTVM. The circuit diagram of a balanced bridge triode VTVM is shown in figure. In this instrument two identical triodes T1 and T2 are used. Plate voltage is applied to both   of the triodes through two, identical resistors...
read more

RMS Reading Voltmeter

jojo September 23, 2009 1 Comment
True RMS Reading Voltmeter RMS value of the sinusoidal waveform is meas­ured by the average reading voltmeter of which scale is calibrated in terms of rms value. This method is quite simple and less expensive. But sometimes rms value of the non-sinusoidal waveform is required to be measured. For such a measurement a true rms reading voltmeter is required. True rms reading voltmeter gives a me­ter indication by sens­ing heating power of waveform which is proportional to the square of...
read more

AC Voltmeters

jojo September 23, 2009 2 Comments
In electronic ac voltme­ters input signal is firstly rectified and then sup­plied to the dc amplifier, as shown in figure. Sometimes signal is firstly amplified by ac amplifier and then recti­fied before supplying it to dc meter, as shown in figure. In the former case the advantage is of economical amplifiers and the arrangement is usually used in low priced voltmeters. AC Voltmeter Block Diagram Broadly ac voltmeters can be divided into three categories. 1. Average Reading AC Voltmeters. AC Voltmeter...
read more