LG ProBeam BF50NST Manuel D'utilisation page 124

Screen Problems
First of all, perform a
for any abnormalities in the projector.
If you are using a set-top box, turn it off, and then turn it back on.
Make sure that the set-top box is correctly connected to your projector.
It says there is no signal on the screen.
•
Make sure that the HDMI® cable is correctly connected to your projector.
•
Go to to choose the connected input.
•
Check if your external device, such as set-top box or Blu-ray player, is turned on.
The screen shakes after the momentary appearance of vertical/horizontal lines
and net pattern.
•
Stop using items such as wireless telephones, hairdryers, electrical drills etc.
The problem is caused by high-frequency electronic devices such as another
projector or strong electromagnetic sources.
(Q. Settings) [Picture] [Picture Test] to check
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