| Designator |
Component Type |
| A | Sub-assembly or plug-in module |
| BT | Battery |
| C | Capacitor |
| D | Diode |
| DS | Display |
| F | Fuse |
| FB | Ferrite bead |
| FD | Fiducial |
| FL | Filter |
| H | Hardware (mounting screws, etc) |
| J | Jack, fixed part of a connector pair |
| JP | Jumper / link |
| K | Relay |
| L | Inductor, coil, ferrite bead |
| LS | Loudspeaker or buzzer |
| M | Motor |
| MK | Microphone |
| P | Plug, movable part of a connector pair |
| Q | Transistor |
| R | Resistor |
| RN | Resistor network |
| RT | Thermistor |
| RV | Varistor |
| SW | Switch |
| T | Transformer |
| TC | Thermocouple |
| TP | Test point |
| U | Integrated circuit (IC) |
| Y | Crystal / oscillator |
| Z | Zener diode |