Yealink SIP-T48U Administrator's Guide

Phone Customization
207
Parameter
features.blf_active_backlight.enable <y0000000000xx>.cfg
Description
It enables or disables the phone to turn on the backlight or stop the screen saver when the BLF/BLF
list status changes.
Permitted
Values
0-Disabled
1-Enabled
Default
1
Supported
Devices
All phones except T19(P) E2 and CP920
Adding a Screensaver Picture from a USB Flash Drive
The T57W/T54W/T48U/T48S/T48G/T46U/T46S/T46G/T29G IP phone enables you to add a screensaver picture
from a USB flash drive on their phones. You can navigate to Menu > USB > Browse Photo, preview pictures, and
then set the desired picture as a screensaver. After you set a picture in USB flash drive as a screensaver, the pic-
ture is added to the Screensaver list.
Note: Yealink phones support USB flash drive in FAT32 or NTFS format.
Related Topic
Custom Screensaver Picture Limit
Deleting a Screensaver Picture
You can delete the uploaded custom pictures for a specific IP phone via the web user interface at the path: Settings
> Preference, select Custom from the Screensaver Type field, and then select a desired custom picture from the
Screensaver field, click Del (Delete). You can only delete the custom pictures.
Backlight
You can change the backlight brightness of the phone screen during phone activity and inactivity. The backlight
brightness automatically changes when the phone is idle for a specified time. It is not available on T19(P) E2
phones.
You can change the screen backlight brightness and time in the following settings:
Active Level: The brightness level of the LCD screen when the phone is active. Digits (1-10) represent different
brightness levels. 10 is the brightest level.
Inactive Level: The brightness of the LCD screen when the phone is inactive. You can select a low brightness or
turn off the backlight.
Backlight Time: The delay time to change the brightness of the LCD screen when the phone is inactive. Backlight
time includes the following settings you can choose from:
l
Always On: Backlight is on permanently.
l
Always Off: Backlight is off permanently. It is not available for the
T57W/T54W/T48U/T48S/T48G/T46U/T46S/T46G/T29G IP phone.
l
15s, 30s, 1min, 2min, 5min, 10min or 30min: Backlight is changed when the phone is inactive after the des-
ignated time (in seconds).
Topics
Supported Backlight Options
Backlight and Time Configuration

Yealink SIP-T48U Specifications

General

Handset type	Wired handset
Product type	IP Phone
Product color	Gray
USB 2.0 ports quantity	USB 2.0 ports have a data transmission speed of 480 Mbps, and are backwards compatible with USB 1.1 ports. You can connect all kinds of peripheral devices to them.
Expansion module support	Yes
Ethernet LAN (RJ-45) ports	2
Display diagonal	7 \
Display resolution	800 x 480 pixels
Lines quantity	- lines
Phonebook capacity	1000 entries
Number of VoIP accounts	16
Voice codecs	AGC, AJB, AMR-WB, CNG, G.711, G.722, G.723.1, G.726, G.729ab, VAD, iLBC
Security algorithms	AES, HTTPS, SRTP, TLS
Ethernet LAN data rates	10, 100, 1000 Mbit/s
Ethernet LAN interface type	Gigabit Ethernet
Front camera	-
AC adapter input voltage	100 - 240 V
Operating temperature (T-T)	0 - 40 °C
Operating relative humidity (H-H)	10 - 95 %
Keypad number of keys	29
Number of handles included	1 pc(s)
Harmonized System (HS) code	85171800

Weight and Dimensions

Width	226 mm
Height	185 mm