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Emitter biasing is when you add a resistor between the emitter of a transistor and the 0v rail so that any voltage developed across the emitter will subtract from the voltage on the base and effectively turn the transistor OFF.
We are talking about an NPN transistor and the transistor is an "ordinary transistor" or BJT (bi-polar Junction Transistor). For more information on transistor biasing see: Talking Electronics website.
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Why is the gain and bandwidth of a ce-cb cascode amplifier greater than a ce amplifier?
Gain of ce-cb cascode is nearly equal to the gain of ce amplifier, because in a ce-cb cascode, the gain of the ce stage is equal to 1, and the gain of the cb stage is nearly equal to an isolated ce amplifier. Hence, gain of both are nearly equal. On the other hand, Bandwidth of ce-cb cascode is much higher than the bandwidth of ce amplifier because the cb stage in the cascode configration is not subjected to any Miller effect, thereby improving the high frequency response. The absence of Miller effect is due to the fact that the base of the cb stage is grounded thus, shielding the collector signal from being fed back into the emitter input. To be more clear, the gain of CE stage in cascode is nearly 1, which reduces the miller effect on the cb stage greatly.
How do you make plane invisible to the radar?
It is not possible (with today's technology) to make a plane completely invisible, but there are techniques to reduce the radar energy being reflected to the radar aerial. If reduced enough, the aircraft may appear smaller than it is, or even be classified by the system or operator as a non-aircraft. The aim is to reduce the Radar Cross Sectional Area (RCA) of the plane.This technology is commonly referred to as 'stealth'. Modern stealth aircraft have an RCA much smaller than 1 square metre and in some circumstances can be as low as that of a large bird.The most noticeable method of reducing RCA is to eliminate right angles and especially internal angles of 90 degrees. This is because energy entering will be reflected straight back the way it came. By using curves and obtuse or acute angles the energy is instead reflected away from the radar source. Use of clean lines and unbroken surfaces also reduces bumps and protrusions which also increase the RCA. By comparing a modern stealth fighter to older aircraft, it is clear that care has been taken to eliminate any feature which would reflect radar energy.Another less obvious technique is to use radar absorbent paint. This expensive material works best against specific wavelengths of radar and will dramatically reduce the reflected energy. It works by allowing a proportion (about 50%) of the energy to be reflected and the remainder to penetrate. If the paint is exactly 1/4 of a wavelength think (hence the expense!) it will reflect off the inner paint surface and be 'antiphase' as it emerges again. This cancels out much of the radar energy in the same way that ripples in a pond from two pebbles cause patterns of high and low ripples.Combinations of techniques such as these can reduce the aircraft RCA to that below the capability of most radars to detect at normal range. As the aircraft approached the radar emitter the radar signal will be increased until it is recognisable as an aircraft. However, by avoiding flying close to radars it may be possible to avoid detection at all, or at the least until it is too late to be a problem for the mission.
What is effect of emitter resistor?
It provide sufficient biasing to the transistor. ANSWER: It purpose is to provide bias and limiting gain.
What is the biasing technique in transistor for it to be in active region?
For a transistor to be in active region : Base Emitter junction should be forward biased and Emitter collector junction should be reverse biased.
Why you use negative source in emitter biasing?
to get the base- emitter junction forward bias we should connect the negative of the diode with the negative of the battery and the positive of the diode with the positive of the diode so we should connect negative source in the emitter
What do you mean by common emitter configuration and biasing pnp transistors?
A common emitter BJT transistor has the emitter ground. So u measure input voltage at base with respect to the ground, i.e; emitter and also u measure the output voltage at collector with respect to the ground, i.e; emitter. Hence, the emitter is common and thus the name.
What is a function of baising?
what is a function of Biasing and explain it's working ? why the Common Emitter Configuration is use as Amplifier ? Explain in Detail ?
Why input gain of an amplifier is doubled from output gain?
The gain of a transister stage is determined by its biasing circuit design. The emitter of a transistor is affected by the input signal on the base. If the base forward biases the transistor, the emitter feels the potential of the colector. If the base reverse biases the transistor, the emitter is isolated from the collector and feels the potential of the emmiter biasing circuit. The output signal at the emmiter is representitive of the signal on the base, 180 degrees out of phase. The amplitude of the output signal will be larger, depending on the biasing circuit design.
Why biasing is needed at all?
Biasing is used in a transistor amplifier circuit in order to place the transistor as nearly as possible in the center of its linear region. Transistors have cutoff, linear, and saturation regions. Too little bias current, and you enter cutoff - Too much, and you saturate. Both conditions cause distortion when you attempt to use the transistor as an amplifier, as opposed to a switch.
Which terminal represents the control input of a bipolar transistor?
baseUmm....Device current results from forward biasing of the emitter-base junction.Thus you can:1. hold the emitter constant and apply control to the base (most common), or2. hold the base constant and apply control to the emitter (common/grounded base circuit, mostly used at high/very high frequencies).
Which biasing is known to as universal biasing?
voltage divider biasing
How biasing of FET differs from biasing of BJT?
in BJT forwardbiasing & reverse biasing are carried out but in FET voltage divider biasing &self biasing are carried out.
Why in common collector amplifier however you change value of resistance not amplifier in voltage?
The question does not quite make sense. It sounds like you are asking why does changing the emitter resistor in a class C common collector amplifier not affect the output voltage? If so, the answer is that the common collector is an emitter follower, meaning that the emitter will follow the base, less the base-emitter junction voltage, within the limits of hFe. The resistor is simply there to ensure output biasing when the base voltage goes low.
What are the types of biasing in pn junction diode?
There are 2 type of biasing in PN junction didoe Forward biasing Reverse biasing
