Definition
An electronic amplifier stage placed between two circuits to isolate them from each other, preventing the load or behavior of one circuit from affecting the operation of the other. A buffer amplifier typically has high input impedance and low output impedance, and often provides little or no voltage gain — its purpose is isolation, not amplification.
Plain English
A small electronic stage that sits between two circuits so they don't interfere with each other. It passes the signal through cleanly without letting one circuit disturb the other.
Context Anchor
Seen in aircraft electronics, instrument circuits, sensor circuits, and avionics troubleshooting descriptions.
Derivation
‘Buffer’ comes from an old English word meaning ‘to absorb a shock’ — the same idea as a railway buffer that keeps two cars from slamming into each other. In electronics, the buffer amplifier absorbs the electrical ‘shock’ between two circuits so neither one disturbs the other.
Why Pilots Care
Maintains signal integrity in communication and navigation systems so data reaches displays and controls without distortion or loss.
Analogy
Think of a buffer amplifier like a person relaying a quiet message to a larger room. The first speaker does not have to shout, and the room still gets the message clearly.
Intuition Check
Do not assume “buffer” means a storage area here. In this electronics use, a buffer mainly separates two circuit sections so one does not disturb the other.
Example Sentence 1
The transmitter's oscillator feeds a buffer amplifier so that changes in the power stage don't pull the oscillator off frequency.
Example Sentence 2
Technicians check the buffer amplifier in the audio panel when microphone signals are weak at the transmitter.