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It doesn't have to be; you can do it either way.
If it's part of a transceiver, then the LO is usually placed on the side of the Rx freq that's
opposite the Tx freq, so that leakage from the Tx oscillators can't produce Rx phantoms.
Another thing to watch out for ... depending on the Rf band and the IF, you wouldn't want
the LO to ever operate AT or near the IF frequency. That could really play havoc with the
Rx discrimination.
For example ... an old AM radio, covering 0.55 to 1.6 MHz, with an IF of 0.455. If you put the
LO on the low side, then at or near 910 on the dial, the LO runs at 455 to produce an IF at 455 !
There's this loud LO blasting out at 455, while the IF strip is trying to work with this tiny received
signal at 455 at the same time. Not good.
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What is the difference between local oscillator and oscillator?
Oscillator is a generic word for any circuit that produces an alternative signal. The shape of the signal, its stability and its output impedance are not considered in this case. "Local oscillator" is one specific type of oscillator used in radio receiver for the purpose of frequency conversion. the input Radio Frequency( RF ) signal is "mixed" with the local oscillator signal and the subtraction of two frequencies is obtained at the output. "Mixing" in this context means: "multiplication"\ In some other context in electronics (specially audio) mixing means "adding" the mathematical operation for local oscillator is F out=Fin - F loc.osc. The output of the mixing operation can also be Fin+F loc.Osc. But this higher frequency is usually filtered out. The local oscillator needs to be a pure sine wave with a very good frequency stability and usually very stable output voltage. Recently very good "synthesizers" are introduced in the market that permit generation "programmable local oscillation"
What is a local oscillation?
A local oscillator is used in a superheterodyne radio circuit for example.The incoming radio frequency is mixed with an internal local oscillator circuit to generate a new intermediate frequency (IF) .The local oscillator usually runs at a frequency of 470kHz and is generated by an inductor and capacitor(LC oscillator)
What is the difference between crystal and local oscillator?
oscillator frequency is different.crystal working piezo electric effect
What is the purpose of a local oscillator in mixer?
A local oscillator is a device that generates a sinusoidal signal with a frequency such that the receiver is able to generate the correct resulting frequency, or intermediate frequency (IF), for further amplification and conversion into audio detection. There is one local oscillator in a single conversion super heterodyne receiver where heterodyning or mixing is used to generate beat frequencies, which may be the sum or the difference of two frequencies. The local oscillator is usually adjustable and in step with the increment or decrement in the receiver frequency. For instance, if the receiver is tuned to 1,455 kilohertz (kHz) as radio frequency input (RF-in), the local oscillator frequency (LOF) may be set to 1,910 kHz for a so-called high side injection. The two signals are fed to an electronic device known as the mixer, which derives LOF - RF-in = IF or 455 kHz, which suggests why amplitude modulation (AM) broadcast receivers have about four stages of low-power amplifiers tuneable to 455 kHz.
What are the principles of mixing in electronic communications?
In receivers the received RF signal is mixed with the signal of a local oscillator of a different frequency and the intermediate frequency is then amplified by the IF stages normally 3 that resonate slightly off beat to filter out all harmonics and is then detected by the detector stage where all RF is filtered down to ground and only pure audio is then amplified In receivers the received RF signal is mixed with the signal of a local oscillator of a different frequency and the intermediate frequency is then amplified by the IF stages normally 3 that resonate slightly off beat to filter out all harmonics and is then detected by the detector stage where all RF is filtered down to ground and only pure audio is then amplified
Why you convert FM signal to IF frequency?
Mix it with a local oscillator whose frequency is (the IF frequency) away from the frequency of the FM signal you're interested in.
What is the use of local oscillator?
A local oscillator generates a radio frequency signal that mixes with the incoming signal in a superheterodyne receiver to produce an intermediate frequency (IF) signal. This IF signal makes it easier to process and extract information from the incoming signal. The local oscillator helps in tuning and filtering the desired signal from the incoming radio frequency spectrum.
What is function of an oscillator?
A local oscillator is an electronic device used to generate a signal normally for the purpose of converting a signal of interest to a different frequency using a mixer. This process of frequency conversion, also referred to as heterodyning, produces the sum and difference frequencies of the frequency of the local oscillator and frequency of the input signal of interest. These are the beat frequencies. Normally the beat frequency is associated with the lower sideband, the difference between the two.
What is the difference between local oscillator and oscillator?
Oscillator is a generic word for any circuit that produces an alternative signal. The shape of the signal, its stability and its output impedance are not considered in this case. "Local oscillator" is one specific type of oscillator used in radio receiver for the purpose of frequency conversion. the input Radio Frequency( RF ) signal is "mixed" with the local oscillator signal and the subtraction of two frequencies is obtained at the output. "Mixing" in this context means: "multiplication"\ In some other context in electronics (specially audio) mixing means "adding" the mathematical operation for local oscillator is F out=Fin - F loc.osc. The output of the mixing operation can also be Fin+F loc.Osc. But this higher frequency is usually filtered out. The local oscillator needs to be a pure sine wave with a very good frequency stability and usually very stable output voltage. Recently very good "synthesizers" are introduced in the market that permit generation "programmable local oscillation"
What is a local oscillation?
A local oscillator is used in a superheterodyne radio circuit for example.The incoming radio frequency is mixed with an internal local oscillator circuit to generate a new intermediate frequency (IF) .The local oscillator usually runs at a frequency of 470kHz and is generated by an inductor and capacitor(LC oscillator)
What is local oscilator?
A local oscillator is used in a superheterodyne radio circuit for example.The incoming radio frequency is mixed with an internal local oscillator circuit to generate a new intermediate frequency (IF) .The local oscillator usually runs at a frequency of 470kHz and is generated by an inductor and capacitor(LC oscillator)
What is the difference between crystal and local oscillator?
oscillator frequency is different.crystal working piezo electric effect
What is the purpose of a local oscillator in mixer?
A local oscillator is a device that generates a sinusoidal signal with a frequency such that the receiver is able to generate the correct resulting frequency, or intermediate frequency (IF), for further amplification and conversion into audio detection. There is one local oscillator in a single conversion super heterodyne receiver where heterodyning or mixing is used to generate beat frequencies, which may be the sum or the difference of two frequencies. The local oscillator is usually adjustable and in step with the increment or decrement in the receiver frequency. For instance, if the receiver is tuned to 1,455 kilohertz (kHz) as radio frequency input (RF-in), the local oscillator frequency (LOF) may be set to 1,910 kHz for a so-called high side injection. The two signals are fed to an electronic device known as the mixer, which derives LOF - RF-in = IF or 455 kHz, which suggests why amplitude modulation (AM) broadcast receivers have about four stages of low-power amplifiers tuneable to 455 kHz.
The FM receiver is tuned 98.3 mhz if 10.7 mhz local oscillator frequency is?
The question probably should be, "If the FM receiver is tuned to 98.3MHz and the IF (intermediate frequency) is 10.7MHz, then what frequency is the local oscillator running at?" The answer would be 87.6MHz but i could be 109MHz and would still work. The local oscillator is mixed with the received signal and what comes out contains both the sum and the difference of the two frequencies. The amplifiers that follow are highly tuned to the IF and so only that frequency is amplified and demodulated by the receiver.
Can a radio receiver be located with a detector?
Yes, a radio receiver can be located with another receiver or tracer, most radio receivers is of the regenerative type and it has a local oscillator that is used to generate an intermediate (IF) signal of 465Khz on shortwave and 10.7Mhz on the higher frequencies like a FM or TV receiver, that oscillator is like a low power transmitter that is transmitting an un-modulated RF signal. Any nearby receiver can pick up this signal although no sound will be heard on the receiver, to be able to hear a signal the tracer is equipped with a BFO, (Beat Frequency Oscillator) that will generate an audible tone when a signal is received, the same way as the local oscillator generate the IF signal but only in the audible frequencies and a signal strength meter, then with a directional antenna, the receiver that is to be traced can be pin pointed.
What is a super heterodyne receiver?
A superheterodyne receiver is a Radio Frequency receiver method that multiplies the received signal frequency with a local oscillator frequency to get frequencies that are the sum and difference of the 2 frequencies. For example, if the received signal is 5MHz and the local oscillator frequency is 4MHz, they are multiplied together. 1MHz and 9MHz frequencies would be gotten. Usually the 1MHz is the Intermediate Frequency (IF). It will be admitted (through a band pass filter) later passed through the required electronic circuits for proper processing. There is also the method of the Variable Tuned Filter.
What is effect of frequency drift and phase drift of local oscillator in synchronous detection of dsb sc demodulation?
Frequency drift of the local oscillator can cause distortion and loss of signal in the demodulated output, while phase drift can lead to phase error which affects the accuracy of demodulation in synchronous detection of DSB-SC modulation. Both drifts can introduce errors and reduce the quality of demodulated signal.
