Definition
An electronic circuit that produces two output signals from a single input signal, with one output identical to the input and the other shifted 180 degrees out of phase with it. Phase inverters are commonly used to drive push-pull amplifier stages, where two equal but opposite signals are required.
Plain English
A small circuit that takes one signal in and gives back two signals: one is the same as the original, and the other is its mirror image. This lets the next stage of a circuit work on both halves of a signal at the same time.
Context Anchor
Seen in aircraft electronic equipment, audio circuits, radio equipment, and maintenance troubleshooting of signal circuits.
Derivation
From Greek 'phasis' meaning 'appearance' or stage of a cycle, and Latin 'invertere' meaning 'to turn upside down.' The name describes exactly what the circuit does — it turns part of the signal upside down relative to the original.
Why Pilots Care
Pilots usually do not operate a phase inverter directly, but a failed phase inverter can affect equipment that depends on clean electronic signals, such as audio or radio circuits.
Analogy
Think of two people on a seesaw: when one side goes up, the other side goes down. A phase inverter creates that kind of opposite motion in an electrical signal.
Intuition Check
Do not confuse a phase inverter with a power inverter that changes DC power into AC power. Here, inverter means the circuit reverses the phase of an existing signal.
Example Sentence 1
The technician traced the fault to a failed phase inverter in the audio amplifier of the aircraft intercom.
Example Sentence 2
Maintenance replaced the phase inverter when the autopilot lost power during a test flight.