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the approximate efficiency of a class b linear RF AM amplifier is 35%
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Why class AB amplifier have high efficiency?
A class AB amplifier of the complementary transistor type has two transistors in series. Both transistors can change the resistance. If the upper transistor, a npn type, has minimum resistance and the lower transistor, a pnp type, has maximum resistance, the output voltage is near the supply voltage. One transistor is totally open and has zero current, the other transistor is totally closed and has zero voltage. Working together both transistors can set the output to any voltage between 0 and supply voltage. The class AB efficiency maximum is 100% minus the bias-power, see for example D. M. Snider, "A Theoretical Analysis and Experimental Confirmation of the Optimally Loaded and Overdriven RF Power Amplifier", 1966. Today the overdriven class AB amps are called class D.
Will analog boster work on didital TV?
I think you mean a (TV antenna amplifier) RF amplifier used with coax cable. The answer is YES it will work with DTV.
What is amplifier and what is the general circuit of amplifier?
An amplifier amplifies voltage or current. The most basic amplifier consists of a transistor where a signal is fed into the base and is output to the emitter or collector. For simple, low frequency applications (not RF), it may be simpler to use an operational amplifier (op amp) than designing your own amplifier. Also, the data sheets provide very helpful schematics for creating an amplifier. A very common one is the 741; these are also fairly cheap.
How can you get clearer pictures in the rooms without a converter box when you are paying for cable TV?
Sounds like you're trying to run several TV's from one cable box's RF output. All you need to do is get an RF amplifier to raise the signal output from the box enough to overcome the losses in the splitters and cable you're using. If you're using just basic cable, the same RF amplifier should work to boost the signal, and it should be placed where the cable is split off for the different feeds to the other TV's. You'd probably be better off putting the amplifier just at the first signal splitter. To determine how much amplification you'd need, just add up the signal loss for each split (usually 3 to 6 db and also 3 db per hundred feet of RG-6 cable). Once you have the total, you need an amplifier just large enough to cancel out the losses. And yes, you can go a little larger with the signal gain, but not too much as you can also over drive the inputs of the TV. In this case, more isn't always necessarily better.
How do you find IF Frequency from RF Frequency?
Transmit RF frequency subtract to the Receive frequency
RF amplifier of an AM receiver is biased in?
class C
What are the Difference Between AF Amplifier and RF Amplifier?
The amp for audio freq. is a AF amplifier. The RF amp is for radio freqs.
What are the two types of rf amplifiers?
A unidirectional amplifier & a Bidirectional amplifier
What is a RF amplifier?
A RF amplifier is a device for electrically amplifying the power of an electrical signal, typically, but not exclusively, radio frequency signals.
Is an rf power amplifier useful in the home?
The answer to whether an RF power amplifier is useful for your home depends on the qualifty if your equipment. If your T.V. is getting a weak signal for example, an RF power amplifier may be useful to get a better signal.
RF amplifier of an AM receiver is normally biased in class a class b class c?
class C because Class C also provides better signal,rejects unwanted signal.class c
What is A or C biasing?
The three standard forms of analog amplifier biasing are:class A - the amplifier is biased in the center of its linear operating range, this is the most linear but least efficient type of amplifier (because the transistors or tubes are always conducting, even when there is no signal to ampliify).class B - the amplifier is biased at the cutoff point, this is an efficient amplifier but is only linear if operated as a push-pull amplifier (because the transistors or tubes are in cutoff and not conducting when there is no signal and through one half of every cycle, a class B push-pull amplifier has two sections that operate on alternate halves of the cycle).class C - the amplifier is biased in hard cutoff so that only the peaks of the input signal are amplified, this is the most efficient amplifier (because the transistors or tubes may be in cutoff and not conducting for more the 85% of the time) but it is not capable of linear amplification. An amplifier biased as class C is only suitable for use in RF transmitter power stages, where a resonant LC tank circuit will be excited into oscillation by the output of the amplifier and complete the missing parts of the cycle.There are other forms of biasing (e.g. class AB) analog amplifiers that get some of the advantages of two of the standard forms. There are also forms of amplifiers having other nonstandard classes (e.g. class D) that are not analog amplifiers, but instead operate by amplifying pulses.
What is selective amplifier?
Selective amplifier is an RF amplifier which selects particular frequency and amplifier so it can operate at fixed frequency.
What is Bandwidth of RF amplifier?
That depends on its purpose. Some examples:RF amplifier in IF stage of AM radio: 10KHz.RF amplifier in TV set: 6MHz.RF amplifier in IF stage of FM radio: 200KHz.An RF amplifier in a military RADAR set will probably have very narrow bandwidth to reduce jamming possibility, but wide enough to allow for doppler shift of targets.
Why class AB amplifier have high efficiency?
A class AB amplifier of the complementary transistor type has two transistors in series. Both transistors can change the resistance. If the upper transistor, a npn type, has minimum resistance and the lower transistor, a pnp type, has maximum resistance, the output voltage is near the supply voltage. One transistor is totally open and has zero current, the other transistor is totally closed and has zero voltage. Working together both transistors can set the output to any voltage between 0 and supply voltage. The class AB efficiency maximum is 100% minus the bias-power, see for example D. M. Snider, "A Theoretical Analysis and Experimental Confirmation of the Optimally Loaded and Overdriven RF Power Amplifier", 1966. Today the overdriven class AB amps are called class D.
An RF amplifier amplifies the incoming signal by 200 times Calculate the power gain of this amplifier in dB?
If an RF amplifier amplifies the incoming signal by 200 times, the power gain of the amplifier is +25.9 dB. Power is proportional to voltage squared, so the power gain is 400. The decibel scale is 3 times log2 of the power change.
Tell you what an intermediate frequency amplifier do?
The intermediate frequency (IF) amplifier lies between the mixer and the demodulator. The mixer shifts the input radio frequency (RF) signal into the range of the IF amplifier. The IF amplifer is a band pass amplifier, so only RF signals that are the IF frequency distance away from the local oscillator in the mixer can pass through to the demodulator. This process is called the superhetrodyne process.
