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The emitter resistor in a common emitter configuration provides negative feedback to the transistor, reducing both its voltage gain and distortion.

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What is effect of an unbypassed resistor on the common emitter amplifier circuit?

An emitter resistor in a common emitter circuit will cause the stage to experience the effects of degenerative feedback if it is unbypassed. The degenerative feedback reduces gain. This is probably the primary effect in the described circuit.


What is collector in transistor?

In a transistor, the collector is one of the three primary terminals, the other two being the emitter and base. It is responsible for collecting charge carriers (electrons or holes) that flow from the emitter through the base, allowing the transistor to amplify or switch electronic signals. The collector typically operates at a higher voltage than the emitter and is crucial for the transistor's functionality in electronic circuits. In bipolar junction transistors (BJTs), it plays a key role in determining the transistor's operating characteristics.


What is reason of invertong output of common emitter amplifier?

The output of the common emitter amplifier is inverted because increasing the base-emitter current causes a proportional increase in collector-emitter current. That increase in collector-emitter current pulls the collector towards the emitter, so the voltage on the collector will go down when the biased base voltage goes up, and vice versa. This is the characteristic of the Class A Common Emitter amplifier. Responding to a request for more details... This is for the NPN transistor. It applies to the PNP transistor as well, but directionality of voltage and current increases is reversed in that case. Start with the base-emitter circuit. You have some kind of bias network holding the base at a certain voltage. That voltage represents a certain current, which goes through the base-emitter junction and emitter resistor, if there is one. Typically, you consider that the emitter voltage is less than the base voltage by the amount of one diode junction, or about 0.7 volts. If you were to increase the input voltage, you would cause a corresponding increase in base-emitter current. The transistor has gain, beta-dc or hFe, which is basically the ratio of collector-emitter current over base-emitter current, so the base-emitter current is controlling a larger collector-emitter current. Now, focus on the collector-emitter circuit. You have some kind of resistor in the collector, and you might have some kind of resistor in the emitter. (More on the emitter resistor later.) Think of this circuit as three resistors in series, the collector resistor, the equivalent resistance of the collector-emitter junctions, and the emitter resistor. This also represents a current, one that is being controlled by the base-emitter resistance. Note that the base-emitter current is being added to the collector-emitter current, so the emitter current, by Kirchoff's current law, is the sum of the base and collector currents. Since the gain is relatively high, however, the contribution from the base is generally negligible. (In high power transistor amplifiers, gain is usually low, so base current is not negligible, so we do take it into account.) The crucial factor here is that the collector current is proportional to the base current, in the ratio of beta-dc, or hFe. If, for instance, base current were increased by 1 ma, with an hFe of 200, then the collector current would increase by 200 ma. Well, sort of.... You have to consider the transistor's limits, and you have to consider whether or not you are opereating in linear mode. Limits are easy, just check the specs. Lets look at linear mode... If you attempt to pull more collector current than the collector-emitter circuit would allow, i.e. to make the equivalant collector-emitter resistance go to zero, then the transistor starts operating in saturated mode. In saturated mode, the transistor is acting as a switch, and it is distinctly non-linear. Even if not saturated, the transistor can be poorly linear when operating at the ends of the linear range. This is why any good design includes consideration of linear mode range. You want to operate in the center of the linear range, which simply means that we bias the base to cause the collector to be in the middle of its optimal range, giving maximum linearity. Summarizing so far, we have a transistor that is multiplying its base current by some factor, beta-dc or hFe, causing a proportional collector current. With this viewpoint, the amplifier is non-inverting because increasing base current causes collector current to increase. We call the circuit inverting, however, because we want to think of the collector voltage rather than the collector current. Remember that the transistor has an equivalent resistance. In particular, the collector-emitter resistance changes in response to stimuli on the base. In order for the collector current to increase, the equivalent resistance must decrease. Looking at the collector-emitter circuit, you have a voltage divider, collector resistance at the top, and the sum of equivalent collector-emitter resistance and the emitter resistance at the bottom. It is easy to see that, if the collector current increases, the collector voltage must decrease. That is why we call this an inverting amplifer. Back to the emitter resistor... When we say "common emitter", we mean that the emitter is common and we analyze everything else. You can design and operate this amplifer with no emitter resistor, and that would be a true common (or grounded) emitter configuration. Problem is the circuit will not be stable... First, gain varies amongst transistors, even amongst transistors of identical design. It is common to state that hFe ranges from 80 to 400, as an example. The circuit design must consider this variability. If you want predictable and stable gain, you must compensate for gain variation. You design the circuit for minimum hFe, but you look at what happens with maximum hFe. To make matters worse, the junction voltage at any particular current varies with temperature, sometimes substantially. This means that your beautifully designed circuit is unpredictable when it gets warm, and all circuits that manipulate power, even small amounts of power, get warm. Its all a matter of degree. There are many ways to compensate for gain variations. One of them is to use an emitter resistor. This effectively places a limit on gain by moving the primary factor for gain from the transistor to the circuit. The gain of a common emitter amplifier is hFe. When there is an emitter resistor, however, the gain is collector resistance divided by emitter resistance. If that ratio is less than hFe, then hFe variability will not affect gain.


How do you check if you have a internal resistor or a external resistor coil?

To determine if you have an internal or external resistor coil, you can visually inspect the ignition coil. An internal resistor coil will have the resistor built into the coil itself, making it more compact, while an external resistor coil will require a separate resistor component in the ignition circuit. Additionally, you can use a multimeter to measure the resistance; internal resistor coils typically have a higher primary resistance (around 1.5 to 3 ohms) compared to external resistor coils. Always refer to the vehicle's service manual for specific resistance values for accurate identification.


Why is the wattmeter connected at the primary side of the transformer?

In general, you can install a wattmeter on the primary or the secondary side of a transformer (it depends what you are trying to measure). But if you are conducting an open- and short-circuit test (to find the transformer's losses), then the wattmeter is connected to the primary side because you want to measure the total (primary + secondary) losses and that is only achievable from the primary side.

Related Questions

What is effect of an unbypassed resistor on the common emitter amplifier circuit?

An emitter resistor in a common emitter circuit will cause the stage to experience the effects of degenerative feedback if it is unbypassed. The degenerative feedback reduces gain. This is probably the primary effect in the described circuit.


What is collector in transistor?

In a transistor, the collector is one of the three primary terminals, the other two being the emitter and base. It is responsible for collecting charge carriers (electrons or holes) that flow from the emitter through the base, allowing the transistor to amplify or switch electronic signals. The collector typically operates at a higher voltage than the emitter and is crucial for the transistor's functionality in electronic circuits. In bipolar junction transistors (BJTs), it plays a key role in determining the transistor's operating characteristics.


What is reason of invertong output of common emitter amplifier?

The output of the common emitter amplifier is inverted because increasing the base-emitter current causes a proportional increase in collector-emitter current. That increase in collector-emitter current pulls the collector towards the emitter, so the voltage on the collector will go down when the biased base voltage goes up, and vice versa. This is the characteristic of the Class A Common Emitter amplifier. Responding to a request for more details... This is for the NPN transistor. It applies to the PNP transistor as well, but directionality of voltage and current increases is reversed in that case. Start with the base-emitter circuit. You have some kind of bias network holding the base at a certain voltage. That voltage represents a certain current, which goes through the base-emitter junction and emitter resistor, if there is one. Typically, you consider that the emitter voltage is less than the base voltage by the amount of one diode junction, or about 0.7 volts. If you were to increase the input voltage, you would cause a corresponding increase in base-emitter current. The transistor has gain, beta-dc or hFe, which is basically the ratio of collector-emitter current over base-emitter current, so the base-emitter current is controlling a larger collector-emitter current. Now, focus on the collector-emitter circuit. You have some kind of resistor in the collector, and you might have some kind of resistor in the emitter. (More on the emitter resistor later.) Think of this circuit as three resistors in series, the collector resistor, the equivalent resistance of the collector-emitter junctions, and the emitter resistor. This also represents a current, one that is being controlled by the base-emitter resistance. Note that the base-emitter current is being added to the collector-emitter current, so the emitter current, by Kirchoff's current law, is the sum of the base and collector currents. Since the gain is relatively high, however, the contribution from the base is generally negligible. (In high power transistor amplifiers, gain is usually low, so base current is not negligible, so we do take it into account.) The crucial factor here is that the collector current is proportional to the base current, in the ratio of beta-dc, or hFe. If, for instance, base current were increased by 1 ma, with an hFe of 200, then the collector current would increase by 200 ma. Well, sort of.... You have to consider the transistor's limits, and you have to consider whether or not you are opereating in linear mode. Limits are easy, just check the specs. Lets look at linear mode... If you attempt to pull more collector current than the collector-emitter circuit would allow, i.e. to make the equivalant collector-emitter resistance go to zero, then the transistor starts operating in saturated mode. In saturated mode, the transistor is acting as a switch, and it is distinctly non-linear. Even if not saturated, the transistor can be poorly linear when operating at the ends of the linear range. This is why any good design includes consideration of linear mode range. You want to operate in the center of the linear range, which simply means that we bias the base to cause the collector to be in the middle of its optimal range, giving maximum linearity. Summarizing so far, we have a transistor that is multiplying its base current by some factor, beta-dc or hFe, causing a proportional collector current. With this viewpoint, the amplifier is non-inverting because increasing base current causes collector current to increase. We call the circuit inverting, however, because we want to think of the collector voltage rather than the collector current. Remember that the transistor has an equivalent resistance. In particular, the collector-emitter resistance changes in response to stimuli on the base. In order for the collector current to increase, the equivalent resistance must decrease. Looking at the collector-emitter circuit, you have a voltage divider, collector resistance at the top, and the sum of equivalent collector-emitter resistance and the emitter resistance at the bottom. It is easy to see that, if the collector current increases, the collector voltage must decrease. That is why we call this an inverting amplifer. Back to the emitter resistor... When we say "common emitter", we mean that the emitter is common and we analyze everything else. You can design and operate this amplifer with no emitter resistor, and that would be a true common (or grounded) emitter configuration. Problem is the circuit will not be stable... First, gain varies amongst transistors, even amongst transistors of identical design. It is common to state that hFe ranges from 80 to 400, as an example. The circuit design must consider this variability. If you want predictable and stable gain, you must compensate for gain variation. You design the circuit for minimum hFe, but you look at what happens with maximum hFe. To make matters worse, the junction voltage at any particular current varies with temperature, sometimes substantially. This means that your beautifully designed circuit is unpredictable when it gets warm, and all circuits that manipulate power, even small amounts of power, get warm. Its all a matter of degree. There are many ways to compensate for gain variations. One of them is to use an emitter resistor. This effectively places a limit on gain by moving the primary factor for gain from the transistor to the circuit. The gain of a common emitter amplifier is hFe. When there is an emitter resistor, however, the gain is collector resistance divided by emitter resistance. If that ratio is less than hFe, then hFe variability will not affect gain.


What is transistor and how can it operate and what are its types?

A transistor is a semiconductor device used to amplify & switch electronic signals. The name transistor comes from the 'trans' of transmitter and 'sister' of resistor. Transistors are used in a wide array of electronic equipment, ranging from pocket calculators and radios to industrial robots and communications satellites.There are two types of transistor viz:Primary type transistor-The primary type of transistor in use is known as a bipolar junction transistor, which consists of three layers of semi-conductor material, two of which have extra electrons, and one which has gaps in it. The two with extra electrons (N-Type) sandwich the one with gaps (P-Type). These bipolar transistor are divided into NPN and PNP types. All these primary type of transistor are shielded to protect from light source if it is not shielded from light then the light may be used to open or close the gate, in which case it is referred to as a phototransistor, functioning as a highly-sensitive photodiode.Secondary type transistor-The secondary type of transistor is known as a field-effect transistor, and consists either entire of N-Type semi-conductive material or P-Type semi-conductive material, with the current controlled by the amount of voltage applied to the transistor.General process of Transistor WorkingEach transistor has a store of electrical charge that remains there until it is turned on. In order to turn on a transistor, a small electrical charge needs to enter it via the base. When this happens, the electrical charge opens up the collector, and a more powerful charge leaves through the emitter. Electrical charge is measured in milliamps, and the typical transistor will multiply an electrical charge by one hundred times the number of milliamps it has. The electrical charge that is emitted by a transistor will then flow through a route designated by however the component it is attached to is designed. Complex electronics have many paths that electrical currents need to travel on, and therefore many transistors will be needed in order to constantly supply enough power to work the device.


The primary winding in a transformer is connected to the what?

The primary winding of a transformer is connected to the supply, while the secondary winding is connected to the load.


What is the purpose of transistor?

A transistor has the same purpose(s) as a triode vacuum tube. It allowed dramatic miniaturization and efficiency improvements, especially when it was figured out how to make monolithic integrated circuits containing them.


What is the term for the transformer winding to which the load is connected?

The load is connected to the transformer's secondarywinding, while the primary winding is connected to the supply. The terms, 'primary' and 'secondary', do NOT relate to voltage levels.


What are the primary winding and secondary winding of a transformer?

The primary winding is the winding connected to the supply, while the secondary winding is the winding connected to the load. The terms, 'primary' and 'secondary' are unrelated to voltage levels.


How can you distinguish the primary from secondaty side on a transformer?

Whichever winding is connected to the supply is the primary winding; whichever winding is connected to the load is the secondary winding.


how does an external resistor connect to ignition coil?

An external resistor connects to an ignition coil by being wired in series with the coil's primary winding. This resistor limits the current flowing to the coil, helping to prevent overheating and ensuring proper voltage levels for the ignition system. Typically, it is connected to the positive terminal of the coil and the ignition switch, while the other terminal of the coil connects to ground. This setup is common in older ignition systems to manage the power output effectively.


Does a 64 falcon have a ballast resistor?

No, it has a primary resistance wire and if you are installing a electronic dizzy you need to bypass this.


Wirings for ignition coil to th resister for a 1972 Datsun pick up truck?

For a 1972 Datsun pickup truck, the ignition coil is typically connected to the ignition switch and the resistor. The resistor is used to reduce the voltage supplied to the coil, ensuring optimal performance and preventing overheating. Generally, the primary wire from the ignition switch connects to one terminal of the resistor, while the other terminal connects to the positive side of the ignition coil. The negative terminal of the coil connects to the distributor or ignition points for spark generation.