Electronics Engineering

Need for modulation

1) to reduce the antenna height

2) to multiplex the more number of signals

3) to reduce the noise & distortions

4) to narrow banding the signal

5) to reduce equipment

If you mean JFET, it is because the gate junction is reverse biased.

Answer It is both 8 bit processors in a 40 pin package but it is not pin compatible, it have almost the same functions but it is very difficult to compare the two because it is not the same family.

7 ohms (5+1+1)

Very carefully

Both are shielded metal welders but differ in the electricity they use. Ac welders can weld heavier metal while dc welders are better for thinner metals. Ac welders can weld magnetized metals. Dc welders can not. The arc in an ac welder is harder to control because of the pulsating current. Dc welders are more expensive. Some welding machines offer both options.

By definition, a solid metal, including liquid mercury, in its elemental form should conduct electricity. Under what condition a metal cannot conduct electricity? Normally when a metal is oxidized, the result is highly resistive, but then the oxide film (such as rust) is no longer considered metallic.

Some metals, such as sodium, don't normally exist in its elemental form in nature. If these metals are somehow kept out of trouble (air), they too should conduct electricity.

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An audio amplifier boosts sound levels. Audio amplifiers typically contain transistors, though the transistors are often packaged inside ICs (Integrated Circuits). A transistor is an electrical device that allows a small amount of voltage or current to trigger a larger level of voltage and/or current. So an amplifier reproduces the sound at a higher amplitude or strength. Of course, there are some tube-type amplifiers that are still in existence. Those are rare and it is hard to find the tubes. Vacuum tubes were what was in use before transistors.

There are different types of audio amplifiers. Radios and televisions contain audio amplifiers to be able to drive the speakers. Once the audio signal is extracted from the radio waves and passes out of the detector stage, it is too weak to drive a speaker.

Sound boards in computers are capable of driving headphones directly, though not always at a comfortable volume. If you want the volume to be louder, or you want to listen through speakers, you would do best to get a set of amplified speakers. They contain an amplifier inside, and that is why they require batteries or a power cord.

Well, if your speaking very basically, a series circuit will have only 1 route to flow, and that's around the entire series circuit. Current leaves the source, and returns to the source, around a single path.

If in doubt with electronics theory, remember this analogy. Electricity is like water in a pipe Voltage= Water pressure (Not directional, doesnt flow in a linear sense)

Current= Rate of water flow (Wider pipes, more current! Resistor's are like kinks in a pipe, limiting flow. This is expressed in Ohm's Law as I=V/R. As R increases, current decreases)

AC, Alternating Current.

An ordinary transformer has two input/output terminals but a center tapped transformer has 2 input and 3 output terminals. One is taken from the center for a ground connection. This causes it to get 50% of the actual value.

And ordinary transformer contains 2 windings.

An autotransformer has one.

DC does not travel through a capacitor for long because there is a buildup of charge on the plates and when the voltage matches the supply voltage, mo more current flows.

But capacitors are used to smooth a DC supply because a capacitor acts a bit like a small battery and can prevent any rapid fluctuations in the supply voltage.

a digital input accepts a voltage level between 0 ( zero and 5 volts +

the digital circuitry is designed to accept a logic 1 or a logic 0 signal .

the logic 1 is equal to 5 volts optimum , but a tolerance is allowed.

the logic 0 signal is around 0 volts, to a limit of 0.8 volts.

thus a digital signal is designed to be at 2 distinct points or levels of measurement.

by comparison an analogue signal can be varying around a designed level.

the input signal is likely to vary and the cirucit inputs are designed to analyse and measure these signals.

All the bulbs will go out.

In a series circuit, the current at all points is the same. This is Kirchoff's Current Law. If you loosen or remove a bulb in a series circuit, the current at that bulb becomes zero, and by Kirchoff's Current Law, the current in every part of the circuit also becomes zero.

You measure current by inserting an amp meter in series with the circuit or using a clamp-on meter to measure current by induction. You measure voltage with a volt meter across the supply. You measure resistance in ohms across the resistance. Luckily all these functions are in the same meter in most cases.

A volt meter is used to measure volts.

So what are volts???

Volts are what a volt meter measures.

Imagine water being pushed through a pipe. If the water in the pipe is falling from a container at a higher place, it goes through the pipe at a higher pressure... sort of like volts.

A larger pipe allows more water through, sort of like amps.

why is extention

Resistance of the circuit = (voltage across the circuit) divided by (current through the circuit)

It became so popular because during the 1920s and so on, and during the Great Depression and World War 1 and such, it was usefull for a new standard in communication with your friends or communication in war but it was also sparked in regular citizens in the U.s and manyother places for leisure. Cause in that time, the radio didnt only broadcast news and music, but dramas, sitcoms, and music programs.

A radio receiver is an electronic device that receives radio wave/signal and convert the information carried by them to a usuable form through speaker. The principal functions of a radio receiver are frequency selection, amplification and detection of signals which are been convert back to its original form through the help of radio speaker.

There is no answer! It depends on the design of the bulb. You can have a 15 watt bulb that is 120 volts or one that is 6 volts. Watts is a measure of power. Volts times amps equals watts. At any given wattage, the higher the voltage is, the lower the amps and viceverca.

The main different between a traditional signal and a message is their recipient. A signal is often sent to a mass of people, while a message is more individualized.

although the AC signal is rectified the output which we get is the pulsating DC which is not desired because many appliances wok on plain DC voltage . The pulsating DC can be viewed as AC + DC component of the signal

ripple factor of a rectified circuit is the ratio of AC component of signal to the DC component of the same rectified output signal. higher the ripple factor says that the signal is not smooth so lesser is its application.

the components used to smooth these type of signals or to remove the 'ripple voltage' as called filters