 Mullard–Philips tube designation

The Mullard-Philips tube designation system is a naming convention used for identifying vacuum tubes (valves) produced by Mullard and Philips. This system includes alphanumeric codes that provide information about the type of tube, its function, and its specifications. The general format of the designation includes several components: 1. **Prefix**: Indicates the tube family or type, such as "12AX7" for a specific type of audio preamplifier tube.