1. Basic knowledge of electronic components--Resistors

Resistance, the symbol is R, the unit is ohm, is a current-limiting element, which represents the size of the obstructive effect of the conductor on the current. It can be divided into wire wound resistors, carbon film resistors, fuse resistors, sensitive resistors, etc., among which sensitive resistors can be divided into varistors, photoresistors, thermistors, etc. according to their sensitive characteristics . It has been widely used in various circuits and has different functions such as voltage division, shunting, impedance matching, and filtering.

2. Basic knowledge of electronic components--Capacitors

Capacitor, the symbol is C, and the unit is Farad. It is a container for holding electricity. It is composed of two metal plates and a layer of insulating medium. It has the characteristics of "passing AC and blocking DC". In the circuit, it has multiple functions such as coupling, filtering, decoupling, resonance, bypassing, neutralization, differentiation, and integration. Like resistance, it is an electronic component that can be seen everywhere in the circuit.

3. Basic knowledge of electronic components--Inductors

Inductance, the symbol is L, and the unit is Henry. It is a component that can convert electrical energy into magnetic energy and store it, also known as choke, reactor, etc. The inductor completes the function of obstructing the current change; the inductor will try to obstruct the current to flow when there is no current flowing; when there is current flowing, it will try to keep the current flowing unchanged. It has the characteristics of "passing direct current and resisting alternating current", and often appears in the form of an LC circuit together with a capacitor.