Every day, facing the board, do you know these letters?

Rx is a resistor, there are many resistors in the circuit diagram, according to the serial number, R1, R2...

Cx is a non-polar capacitor, anti-interference capacitor at the input of the power supply

IC integrated circuit module

Ux is an IC (Integrated Circuit Component)

Kx is different from different manufacturers' component library definitions.

Tx is the test point (for factory testing)

Spk1 is Speaker (buzzer, speaker)

Qx is a triode

Jx is Jack (like Audio Jack)

Y1 different manufacturers have different component library definitions

In addition, there are CEx-electrolytic capacitors, CNx-discharge (several capacitors together), RNx-exclusion, CONx-connector, Dx-Diode (diode), Hx-hole, JPx-Jumper, Lx-inductor/ Magnetic beads, LEDx-LEDs, Xx-crystal.

Each manufacturer has its own component library, and the components when drawing the circuit diagram are all taken from the library (large factory). For some uncommon, such as CON, JP, the definition of each manufacturer will be different.

R (resistance)

FS (insurance tube)

RTH (Thermistor)

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

CX (X capacitor: high voltage film capacitor, safety)

D (diode)

C (capacitor)

Q (transistor)

ZD (Zener diode)

T (transformer)

U (IC chip)

J (jumper)

VR (adjustable resistance)

W regulator

K switch class

Y crystal oscillator

R107, C118, Q102, D202, etc. are often seen on the board. In general, the first letter identifies the device type, such as R for resistors, C for capacitors, D for diodes, Q for three-stage tubes, etc. The two are numbers, indicating the circuit function number, such as "1" for the motherboard circuit, "2" for the power circuit, etc., which is determined by the circuit designer; the third and fourth bits indicate that the device is on the board. The serial number of the same type of device.

R117: The resistance on the main board, serial number 17.

T101: Transformer on the main board.

SW102: switch

LED101: LED

LAMP: (indicator) light

Q104 (E, B, C): Transistor, E: Emitter, B: Base, C: Collector

EG: "If R117 is a resistor, it should be connected with a multimeter at both ends." It is unscientific to measure the resistance directly on the circuit board. The measurement result will be smaller or even smaller than the actual value. It is best to solder out. One lead is measured again.