A simple wide-band sine wave quadrature oscillator

A simple sine wave oscillator delivering two signals in quadrature has been developed. It covers the frequency range from below 1 Hz to 100 MHz and is voltage-controllable over each frequency decade. The circuit consists of two 90 degrees phase shift stages using active allpass filters and an inverter, all arranged in a feedback loop. Although general application is envisaged, the design is particularly suitable in particle electrorotation studies.<
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