Under what operating condition does a silicon controlled rectifier (SCR) exhibit electrical characteristics similar to a forward-biased silicon rectifier?

An SCR is designed to block current until a specific signal is applied to its gate terminal. When the SCR is gated "on" (triggered), it breaks down its internal blocking junction and allows current to flow freely from anode to cathode. In this gated "on" condition, the device is functionally identical to a standard forward-biased silicon rectifier (or diode). It will conduct current in one direction with a small, predictable voltage drop across the anode and cathode. If the device were gated "off" or untriggered, it would behave like a reverse-biased diode, acting as an open circuit. It is not used as an RF detector, nor does its stable characteristic resemble a forward-biased diode during the brief, unstable switching transition itself.