[ICF-1800] How to set up the BLF function in the ICF-1800.

Before we start, please be reminded your IPPBX must also support BLF function.
In Function key/EXT Key.
Type: Please choose Memory Key
Value: Your BLF extension
Line: Choose which line you want to use for BLF function
Subtype: BLF
Media: Select default to allow audio to communicate; you can modify video for communication