In PCB board sampling, Rx is a resistor. There are many resistors in the circuit diagram, arranged in sequence, R1, R2...

　　Cx is a non-polar capacitor, an anti-interference capacitor at the power input end

　　IC integrated circuit module

　　Ux is an IC (Integrated Circuit Component)

　　Tx is a testing point (used for factory testing)

　　Spk1 is a speaker (buzzer, horn)

　　Qx is a transistor

　　CEx electrolytic capacitor, CNx discharge capacitor, RNx discharge resistor, CONx connector, Dx diode, Lx inductor/magnetic bead, LEDx light-emitting diode, Xx crystal oscillator.

　　RTH (Thermistor)

　　CY (Y capacitor: high-voltage ceramic capacitor, safety standard)

　　CX (X capacitor: high-voltage thin film capacitor, safety regulations)

　　D (diode)

　　W voltage regulator tube

　　K switch type

　　Y crystal oscillator

　　R117: The resistor on the motherboard, serial number 17.

　　T101: Transformer on the motherboard.

　　SW102: Switch

　　LED101: Light Emitting Diode

　　LAMP: (indicator) light

　　Q104 (E, B, C): transistor, E: emitter, B: base, C: collector