User Guide

Quick-Start Guide
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Manual Revision: January 17, 2023 8:29 AM
Product ID
ST121HD20FXA2
Transmitter
Receiver
Component Function
1 Power LED Indicator
• Transmitter and Receiver: Solid Red when the
Universal Power Adapter is connected
HDMI over Fiber Extender - 4K 60Hz
2
Optical Signal LED
Indicator
• Transmitter and Receiver: Solid Green when
the Transmitter and Receiver establish an
optical link
3 HDMI Signal LED Indicator
• Transmitter: Solid Green when an HDMI Source
Device is connected to the HDMI Input Port
• Receiver: Solid Green when an HDMI Display
Device is connected to the HDMI Output Port
4 IR Input Port
• Transmitter and Receiver: Connect an IR
Receiver
5 IR Output Port
• Transmitter and Receiver: Connect an IR
Blaster
6 Audio Input Selector
• Change between HDMI Audio Pass-through, or
Line In
7 EDID Selector
• Set the EDID mode for the HDMI Extender
• 11: Copy Receiver’s HDMI Output EDID
• 10: Copy Transmitter’s HDMI Output EDID
• 01: Force 4K 60Hz EDID
• 00: Force 1080P EDID
8 Service Port
• Transmitter and Receiver: For manufacturer
use only
9 DC 5V Input
• Transmitter and Receiver: Connect the
Universal Power Adapter
10 Optical Connection Port
• Connect the Transmitter and Receiver with a
Single Mode or Multi Mode Fiber Optic Cable
• The LC Simplex SFP Module is pre-installed
• Third Party SFP Module’s cannot be used
11 HDMI Output Port • Connect an HDMI Display Device
12 HDMI Input Port • Connect an HDMI Source Device
13 Line In Port • Connect a 3.5mm Audio Device
14 Serial Terminal Block
• Transmitter and Receiver: Connect a RS232
Serial Device to the Terminal Block for bi-
directional communication
15 Audio Output • Connect to an Audio Output Device
1 2
3
4 5
6 7 8
9 10 11 12 13 14
1 2 3 4 5 8
9 10 11 15 14