In order to use a Yealink W52 handset with your Yealink base, you'll first have to pair it to your base. To do this:

• Long press the button on the base station. The registration LED slow flashes, indicating the base station is in registration mode.
• Press OK on the handset to enter the main menu.
• Select Registration > Register Handset. The LCD screen then displays Base 1 - Base 4.
• Press the arrow keys to highlight the desired one, and then press the OK soft key. The handset begins to search for the base station.
• Press the OK soft key when the LCD screen displays the RFPI code of the base station.
• Enter the system PIN (default: 0000)
• Press Done. The handset plays a successful tone and prompts “Handset Subscribed”, which indicates the handset is registered successfully. After successful registration, an internal handset number and handset name appear on the LCD screen.