T42 Users Guide

How to use the Yealink T42

VoIP Introduction

Understanding the difference between traditional phone lines and VoIP (voice over internet protocol)

There are no more "lines"

You might be used to having a certain amount of phone lines in your business. Say you had 5 lines – that meant only 5 people could be on the phone. 

Not true with VoIP. There are no more "lines". 

You can have as many incoming/outgoing calls as you'd like (as long as your bandwidth can handle it). 

This really just means that you no longer have to push a line button to make a call. Or pick up a call from a certain line. 

Phone Anatomy

Voicemail indicator light

This light will blink red when you have a voicemail or a missed call.

Display screen

The display screen gives you access to the phone menus, soft key commands and other programmable information.

Soft keys

Soft keys are buttons that can change functions depending on the status of your phone. They are not associated with a single fixed function like other buttons.

Navigation buttons

Use these buttons to navigate through the menus on your phone.


Easily mute your phone with this button. Button turns red when active.


When a headset is active, this button lights up green.


Easily access your voicemail box by pressing the voicemail/message button.


Redial the last number called.

Speaker phone

Press this button to put a call on speaker phone.

Answering a Call

3 ways to answer an incoming call

Placing a Call

Placing a call (internal & external)

Pick up handset and begin dialing the number or extension. Dialing 9 or any other number to get an outside line is not necessary.

Begin dialing the number (handset cradled). The number will appear on the screen. Pick up the handset and the call will be placed.