Is the signal measured by the induction test pen a magnetic field or an electric field?
Induction test pen, generally test alternating current. The alternating electric field and alternating magnetic field around the alternating current are perpendicular to each other. It's actually an electromagnetic field. Remember and seize the Oster experiment:
Oersted's experiments show that there is a magnetic field around an energized wire as well as around a permanent magnet. Oersted's experiment revealed a very important essence - there is a magnetic field around the current, and the current is generated by the directional movement of the electric charge, so the magnetic field around the energized wire is essentially generated by the moving electric charge. This phenomenon was first discovered experimentally by Danish physicist Oster in July 1820.
When the circuit is in a normal state, Q1 forms a leakage current due to the floating gate, no current flows into the base of Q2, and Q3 is in an extinguished state. When the induction plate is close to the AC power supply of 220V or above, because the power supply will form an alternating electric field around it, the induction plate will induce the corresponding alternating voltage and add it to the gate of Q1. When the induced voltage on the induction plate is negative, Q1 Cut off, V voltage is added to the base of Q2 through R1 and Q4, Q2 is turned on, and Q3 emits light. electrical circuit, which produces current). It becomes a unidirectional current through the diode, and then amplified by the triode, and finally reaches the light-emitting diode.
I analyzed, the induction test pen, the induced signal is: the alternating electromagnetic field around the alternating current (generated induced electromotive force, input direct current
