PLANET UP-121 - Manual (Page 8)

3． Key Features
Key Descriptions
F1
Skype’s TAB key, you can turn pages in the Skype’s “Contacts/Dial/Call list”
Choose between friends list/dialed number/received calls/missed
calls/balance in the menu of the USB phone
F2
Dial or pick up calls Call
Hang up and exit the menu and return to waiting status Hand up
Choose menu option / control the volume in calls Up/Down
Backspace/clear numbers Backspace
Change the ring tone Ring
Number keys (Note: press 0 for a long time means “+”) 0-9/*, #
Mute function in calls Mute
Speaker No use. It is required to have another model (UP-120) for the functionality.