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The purpose of biasing an amplifier is to shift its operating point, so that when you apply a signal in you will get a expected signal out. The operating point is generally in the middle of the linear region. You would not use AC for the bias, as that would cause the operating point to constantly shift, and you would then not be able to differentiate between the signal and the bias.

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Q: Why you are giving dc supply for biasing the amplifier why not ac?
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What is difference between transistor and bias?

"Biasing" applies to transistor amplifier circuits. Simple amplifier circuits can only amplify positive signals. Negative signals cause the amplifier to shut down. However, AC signals in general have both a positive and a negative part. To allow a transistor to amplify AC, we add a positive voltage to the AC signal. Then after it is amplified, we remove the positive voltage again. The voltage, ac or dc on the base, compared to the emitter to cause operation of the transistor to conduct to the collector or to the emiiter in a NPN transistor.


Where is the ac amplifier located on 1999 Geo Tracker?

never heard of a ac amplifier


Is transformer an amplifier?

No. In an amplifier, Power Out > Power in. In a transformer Power Out ~= Power In (minus internal losses). An AC generator is more like an amplifier than a transformer.


Can an ac amplifier amplify the DC signals?

An amplifier generally amplifies an AC waveform (such as sound), and is powered by a DC source. The majority of the power at the output is then coming from a DC source (the power supply in a power amplifier will convert the 50/60Hz AC power in to DC for the amplifier circuitry). So you can make the argument the above (question) is a true statement. But an amplifier wouldn't be used to convert from DC to AC power (in general).


Why do transformers work only work on an AC supply?

Transformers only work on ac supply because it principle is mutual induction. DC supply has constant magnitude whereas AC has alternating magnitude. so we can step up or step down current/voltage in transformer in ac only.

Related questions

Can an amplifier can be operated on ac supply?

Yes, an amplifier can be operated on ac supply.


What is difference between transistor and bias?

"Biasing" applies to transistor amplifier circuits. Simple amplifier circuits can only amplify positive signals. Negative signals cause the amplifier to shut down. However, AC signals in general have both a positive and a negative part. To allow a transistor to amplify AC, we add a positive voltage to the AC signal. Then after it is amplified, we remove the positive voltage again. The voltage, ac or dc on the base, compared to the emitter to cause operation of the transistor to conduct to the collector or to the emiiter in a NPN transistor.


Where is the ac amplifier located on 1999 Geo Tracker?

never heard of a ac amplifier


Why to short circuit capacitor in small signal analysis of BJT?

if the input signal passes through the biasing resistors, the biasing conditions get altered . To prevent this, the input signal should be directly sent to the amplifier (BJT) .Since a capacitor acts as a short circuit for ac signals,capacitors are placed both in the input side and the output side.


Why amplifier does not uses ac to work?

ac is not used because it produces distortion in the output. and also in the transistor the Q point is not able to be fixed by using ac supply. Q point gives the quality output to the amplifiers


Can a 12 volt battery charger use to power a 12 volts amplifier?

The battery charger can be used but it is not recommended. The battery charger does not have filtering on the its output like a power supply does. You will probably hear an AC ripple on the amplifier which will become very annoying when listening to the amplifier.


What is chopper amplifier?

In a chopper type amplifier the dc i/p voltage is converted into an ac voltage, amplified by an ac amplifier and then converted back into a dc voltage proportional to the original i/p signal


Why we use blocking and by pass capacitor in CE amplifier?

As the DC component in the signals are not required to be amplified, rather not required at times. Thus a blocking capacitor blocks this DC component from.entering the amplifier. Bypass capacitors are used at the emitter end so that the AC signal reaching the emitter end does not alter the biasing required to maintain the Q-point. All the above happens using the basic characteristic of a capacitor, that it blocks DC and passes AC.


Is transformer an amplifier?

No. In an amplifier, Power Out > Power in. In a transformer Power Out ~= Power In (minus internal losses). An AC generator is more like an amplifier than a transformer.


Basic theory of two stage RC coupled amplifiers?

connections are to be made per the crkt the main of this crkt is to make strong or to bost the signal comming to the crkt input is given with ac supply and they are connected to resistor and capacitor when the ac suppply is given it contains slight amount of dc supply so to block the dc supply capacitor is used and the dc supply is given at the collector so that resistor present at c and ground gets biased then another capacitor used at c to ground for removing the dc supply then out put seen on cro across collector to ground we get the perfect amplified signal the more we give the coupled amplifer the most amplfed sgnal we get


Why ac current attract?

As we touch an ac supply in which due to body resistance , we create a phase difference between the ac supply and us . As ac reverses polarity , so do we , but our polarity change is opposite to that of the polarity change of ac supply , hence our body gets attracted to the ac supply .


What are Ac load lines in an amplifier and how they are drawn?

The dc load resistance is Rc but the AC Load resistance is (RcRl). If a load line is drawn the slope of which is -1(Rc Rl) . Then it is called an AC load line and it is to be used when the transistor is operating as an amplifier.