VCXO
The voltage controlled crystal oscillator (VCXO) works by controlling the voltage to change the capacitance of the varactor diode, thus "pulling" the frequency of the quartz resonator to achieve the purpose of frequency modulation. VCXO is mostly used in phase lock technology, frequency negative feedback system and frequency modulation, and has been a key component of communication machines, mobile phones, pagers, global positioning system (GPS) and many other electronic applications.
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