Phase-Shift Networks

There are two fundamentally different types of variable phase-shift networks. One type provides frequency-independent variable delays. The other type provides frequency-dependant variable delays. Most commonly-used electronic networks, such as RL, RC, and RLC, provide frequency-dependant variable delays. Very few networks have been devised that provide controllable variable-delays with negligible frequency-response changes. One simple network with that unusual and often desirable flat-frequency-response characteristic sums the outputs from a series capacitor and a series resistor that are being driven by equal-amplitude, opposite-polarity signal-source voltages. ©2004 Tigertek, Inc. All rights reserved.

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