Definition
A handheld electronic test instrument used to detect and indicate the logic state (high, low, or pulsing) at a point in a digital circuit. The probe tip is touched to a circuit node, and indicator lights or tones show whether that point is at logic 1 (high voltage), logic 0 (low voltage), or rapidly switching between the two.
Plain English
A pen-shaped tool a technician touches to a wire or pin inside a digital circuit to see whether the signal at that spot is on, off, or pulsing. Lights on the probe show what is happening so the technician can find faults.
Context Anchor
Seen in avionics and aircraft electrical troubleshooting, especially when checking electronic control units, radio equipment, or circuit boards.
Derivation
From 'logic,' meaning the binary on/off states used in digital electronics, and 'probe,' a slender tool used to reach into something and test it. Together: a tool that probes for logic states.
Why Pilots Care
Allows quick verification of digital signals during maintenance of aircraft electronics.
Intuition Check
Logic does not mean human reasoning here. It means the voltage state used by a digital circuit to represent on, off, or a changing signal.
Example Sentence 1
The avionics technician used a logic probe to trace a faulty signal in the transponder's digital circuit board.
Example Sentence 2
During bench testing the avionics unit, a logic probe confirmed the clock line was pulsing correctly.