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There are two kinds of crystal oscillators. One operates at what is called the "series resonance" of the crystal. This resonance is the frequency at which the (AC) impedance between the pins of the crystal is almost zero. The frequency is independent of how much capacitance happens to be in parallel with the crystal - its inside the oscillator and part of the circuit board, etc. But, even frequency that the oscillator runs at.
The other kind of oscillator oscillates at "parallel resonance"of the crystal. At this frequency, the impedance from pin to pin of the crystal is almost infinite. This frequency depends on how much capacitance is connected in parallel with the crystal. This parallel capacitance is called "load capacitance". Generic signal-inverter oscillator is this kind of oscillator.
The common oscillator connection is for the crystal to be connected from the inverter output to the input. And, there is a capacitor at each end of the crystal to ground. The NET load capacitance is SERIES equivalent value of those two capacitors.PLUS stray capacitance from the circuit board and the guts of the oscillator. Suppose that the crystal is rated for 22pF load capacitance. The stray capacitance is about 7pF. So, that leave 15pF to be made up from discrete external capacitors. If the external capacitors are equal, then their equivalent is half of their individual value. Thus, in this case, we would want a pair of 30pF capacitors.
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Why is a crystal oscillator required in a radio transmitter?
SOME kind of oscillator is required, to create the AC signal that will be modulated, amplified, and eventually sent up to the antenna to be transmitted. It doesn't have to be a crystal oscillator, though.
Why crystal oscillator used for microcontrollers?
Oscillators are connected externally with the microcontroller to provide high frequency signal to the oscillator circuit in the microcontroller. The oscillator circuit provides the clock signal to the micro controller. Usually "PIEZO CRYSTAL OSCILLATORS" are used in micro controllers.
What is a mechanical oscillator?
pendulum spring tuning fork quartz crystal
Why you connect 6.28MHz crystal oscillator in 8085microprocessor instead of 3.14MHz crystal oscillator?
Internally two crystal oscillator cycles are used as one single cycle. During one single crystal cycle it is made to logic high and logic low in next cycle so, that 50% duty cycle is maintained.
What radios have 365 pf tuning capacitors?
AM broadcast - 535~1605 kHz tuning range. The 365 pF cap is most likely in the aerial circuit, as most modern receivers would use a smaller-value section for local oscillator tuning. Alternately, a set may use the *same* value for aerial and local oscillator, with a padding capacitor to reduce the effective max value of the oscillator section.
Why you use capacitors with crystal oscillator?
To increase the efficiency. Comparison between crystal oscillator and ceramic resonator.
Why Two 33pF capacitors are used with crystal oscillator?
c1 and c2 capacitors with crystal eliminates the Harmonics(Unwanted frequencies) .
Is a crystal oscillator built in to integrated circuits?
The crystal oscillator is not built in to integrated circuits, but many devices such as microprocessors and clock generators do provide circuitry that makes it easy to add a crystal of a desired frequency. Some devices will do that with only the crystal added, while some also require small capacitors to stabilize the feedback loop.
What is the difference between crystal and local oscillator?
oscillator frequency is different.crystal working piezo electric effect
Which oscillator produces 1MHz frequency?
crystal oscillator
Why you use capacitor with crystal in microcontroller circuit?
it provides stabilization to oscillator
What type of oscillator used in handwatches?
a crystal 32.768kHz oscillator.
Why crystal oscillator called clap oscillator?
armstron osillator and work
Is RC phase shift oscillator more stable than a crystal oscillator or not?
no
Why is a crystal oscillator required in a radio transmitter?
SOME kind of oscillator is required, to create the AC signal that will be modulated, amplified, and eventually sent up to the antenna to be transmitted. It doesn't have to be a crystal oscillator, though.
Why you use crystal in 8051 microcontroller?
for accurate time rc oscillator is common in non time critical stuff
What is the purpose of an oscillator crystal?
"A circuit within a computer that creates a series of pulses that pace the computer's electronic system. The oscillator clock synchronizes, paces and coordinates the operations of the computer's circuit." -- webopedia
