Tripp Lite B127M-101-H Owner's Manual page 11

Standard Extender Kit Installation
8. Turn on the power to the HDMI source. The OUTPUT (orange)
LED on the local splitter unit will illuminate to indicate a
signal is being received from the source.
9.
The (orange) RJ45 LED will illuminate on both the local
splitter and remote receiver units to indicate a signal is being
received from the source to display. The screen should now
display on the connected monitor(s).
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