Oscillator is an electronic device used for the purpose of generating a signal. They are often found in computers, wireless receivers and transmitters, and audio-frequency equipment, and music synthesizers. They provide the signal source for all microwave systems, including both transmitters and receivers. They can generate a frequency source such as wave or square wave. Microwave oscillators are useful in applications like audio signal generation, reference signals for different applications and in measurement applications. Square wave oscillators are most often used as clock sources for digital electronics circuits and similar applications. Microwave crystal oscillators have spectrum applications ranging military and aerospace applications in communication, electronic warfare, navigation, radar etc. in consumer electronics such as cable TV systems, Cellular and cordless, home computers, phones, pagers, VCR, video cameras etc. They are offered in parameters differing in oscillation frequency, total frequency stability, and RF connector type.