Samsung ua43j5100 User Manual page 56

Source: To select the source of the content that will play when the TV turns
on. You can:
–
Select
–
Select
device.
–
Select a source on your TV (HDMI1, HDMI2/DVI, AV, Component, etc.)
that you have connected a set-top box to, and have the TV display a
channel from the set-top box.
N
The USB device must be connected to your TV before you can select
◀
USB.
TV and have the TV display a specific air or cable channel.
USB and have the TV play back photo or audio files from a USB
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