Tekvox SCU21T-KVM User manual

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SCU21T-KVM
79121-KVM User Manual
SCU21T-KVM
4K 2x1 HDMI/USB-C Switcher
& HDBaseT Receiver
All Rights Reserved
Version: 79121-KVM_2022V1.0

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SCU21T-KVM
79121-KVM User Manual
Preface
Read this user manual carefully before using the product. Pictures shown in this manual are for
reference only. Different product model specifications may vary.
This manual is only for operation instruction, please contact the local distributor for maintenance
assistance. The functions described in this version were updated April, 2022. In order to continue
improving the product, we reserve the right to make function or parameter changes without notice or
obligation. Please refer to the dealers for the latest details.
FCC Statement
This equipment generates, uses, and can radiate radio frequency energy and, if not installed and
used in accordance with the instructions, may cause harmful interference to radio communications.
It has been tested and found to comply with the limits for a Class A digital device, pursuant to part
15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful
interference in a commercial installation.
Operation of this equipment in a residential area is likely to cause interference, in which case the
user at their own expense will be required to take whatever measures may be necessary to correct
the interference.
Any changes or modifications not expressly approved by the manufacture would void the user’s
authority to operate the equipment.

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Safety Precautions
To ensure the best performance from the product, please read all instructions carefully before using
the device. Save this manual for further reference.
•Unpack the equipment carefully, and save the original box and packing material for possible
future shipment
•Follow basic safety precautions to reduce the risk of fire, electrical shock, and injury
•Do not dismantle the housing or modify the module (electrical shock or burn hazard)
•Using supplies or parts not meeting the products’ specifications may cause damage,
deterioration, or malfunction
•Refer all servicing to qualified service personnel
•To prevent fire or shock hazard, do not expose the unit to rain or moisture, or install this
product near water
•Do not put any heavy items on the product’s power cable
•Do not remove the housing of the device, as opening or removing the housing may expose you
to dangerous voltages or other hazards
•Install the device in a place with sufficient ventilation to avoid damage caused by overheating
•Keep the module away from liquids
•Spillage into the housing may result in fire, electrical shock, or equipment damage. If an object
or liquid falls or spills on to the housing, unplug the module immediately.
•Do not twist or pull by force ends of the optical cable. It can cause malfunction.
•Do not use liquid or aerosol cleaners to clean this unit. Always unplug the power to the device
before cleaning.
•Unplug the power cord when left unused for a long period of time
•Information on disposal for scrapped devices: do not burn or mix with general household
waste, please treat them as normal electrical wastes

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79121-KVM User Manual
Table of Contents
1. Product Introduction ....................................................................................................................6
1.1 Features...............................................................................................................................................6
2. Specifications ..............................................................................................................................7
3. Panel Description.........................................................................................................................9
3.1 Transmitter..........................................................................................................................................9
3.1.1 Front Panel .................................................................................................................................9
3.1.2 Rear Panel.................................................................................................................................10
3.2 Receiver .............................................................................................................................................11
3.2.1 Front Panel ...............................................................................................................................11
3.2.2 Rear Panel.................................................................................................................................11
4. EDID Management......................................................................................................................12
5. GUI Control ................................................................................................................................13
5.1 Video Tab...........................................................................................................................................14
5.2 Configuration Tab .............................................................................................................................14
5.2.1 EDID...........................................................................................................................................14
5.2.2 Auto-Downscaling....................................................................................................................15
5.2.3 HDCP.........................................................................................................................................15
5.2.4 Tags ..........................................................................................................................................16
5.3 CEC Tab .............................................................................................................................................17
5.3.1 Input ..........................................................................................................................................17
5.3.2 Output .......................................................................................................................................17
5.3.3 User-Defined.............................................................................................................................18
5.4 RS232 Tab .........................................................................................................................................18
5.5 Network Tab ......................................................................................................................................19
5.6 Access Tab........................................................................................................................................20
6. RS232 Control............................................................................................................................21
6.1 System Control..................................................................................................................................21
6.2 Source Control...................................................................................................................................23

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SCU21T-KVM
79121-KVM User Manual
7. System Connection ....................................................................................................................27
8. Panel Drawing ............................................................................................................................30

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SCU21T-KVM
79121-KVM User Manual
1. Product Introduction
TEKVOX’s SCU21T-KVM is a 4K 2x1 HDMI/USB-C switcher with simultaneous HDMI and HDBaseT
video outputs, audio de-embedding, and automatic source detection & switching. The switcher is
capable of transmitting 4K video, audio, RS232 control, bi-directional 48V PoC, USB
camera/microphone feeds, and Ethernet LAN up to 100m (328ft) via HDBaseT. Connected user
laptops can access and use any USB devices connected to the DEVICE ports on either the switcher
or its receiver, and the USB-C input supports up to 60W charging for connected devices.
With its streamlined yet versatile design, the SCU21T-KVM is the perfect switcher for sophisticated,
modern video conferencing in any space and any application.
1.1 Features
•HDMI and USB-C (with 60W charging) video inputs
•USB-B and USB-C USB hosts for video conferencing and touchscreen connection
•Supports 4Kx2K@60Hz 4:4:4 resolutions, HDR10
•Supports automatic source detection and switching
•Controllable via RS232, CEC, or front panel buttons
•Simultaneous HDMI and HDBaseT video outputs
•100m (328ft) HDBaseT transmission with bi-directional 48V PoC

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2. Specifications
Transmitter
Receiver
Video
Inputs
1x HDMI (19-pin, Type-A,
Female)
1x USB-C (Type-C, Female)
1x HDBaseT (RJ45, Female)
Input Resolution
HDMI: Up to 4Kx2K @ 60Hz
4:4:4, HDR10, Dolby Vision
USB-C: Up to 4Kx2K @ 60Hz
4:4:4
Up to 4Kx2K @ 60Hz 4:2:0
Outputs
1x HDMI (19-pin, Type-A,
Female)
1x HDBaseT (RJ45, Female)
1x HDMI (19-pin, Type-A,
Female)
Output Resolution
HDMI: Up to 4Kx2K @ 60Hz
4:4:4, HDR10, Dolby Vision
HDBaseT: Up to 4Kx2K @ 60Hz
4:2:0
Up to 4Kx2K @ 60Hz 4:4:4,
HDR10, Dolby Vision
Compliances
HDMI: Up to 2.0b
HDCP: Up to 2.2
Audio
HDMI Embedded Audio
Format
LPCM 7.1 audio, Dolby Atmos®, Dolby® TrueHD, Dolby Digital® Plus,
DTS:X™, and DTS-HD® Master Audio™ pass-through
Audio Output
1x Balanced Stereo (5-pin
terminal block)
1x Balanced Stereo (5-pin
terminal block)
Frequency Response
20Hz ~ 20kHz, ±3dB
Maximum Output Level
0.88VRMS ±0.5dB (2V = 16dB above -10dBV (316 mV) nominal
consumer line level signal
Total Harmonic Distortion
+ Noise (THD+N)
< 0.05% (-80 dB), 20 Hz –20 kHz bandwidth, 1 kHz sine at 0 dBFS
level (or max level)
Signal-to-Noise Ratio
(SNR)
> 80dB, 20Hz ~ 20kHz bandwidth
SPDIF: >90dB, 20Hz ~ 20kHz bandwidth
Crosstalk Isolation
< -80dB, 10kHz sine at 0dBFS level (or max level before clipping)
L-R Level Deviation
< 0.3dB, 1kHz sine at 0dBFS level (or max level before clipping)

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Output Load Capability
1kΩ and higher (supports 10x parallel 10kΩ loads)
Noise Level
> 70dB @ 1kHz
Control
Control Ports
1x EDID Switch (4-pin DIP
switch)
2x DEVICES (USB 3.0, Type-A,
Female)
1x ETHERNET (RJ45, female)
1x Firmware (Micro-USB,
Female)
1x HOST (USB 3.0, Type-B,
Female)
2x GR (3-pin terminal block)
2x RS232 (3-pin terminal block)
1x TCP/IP (RJ45, Female)
3x DEVICES (USB 2.0, Type-A,
Female)
1x DEVICES (USB2.0, Type-C,
Female)
1x ETHERNET (RJ45, Female)
1x RS232, 3-pin terminal block)
General
Operating Temperature
23 ~ 131°F (-5 ~ 55°C)
Storage Temperature
-13 ~ 158°F (-25 ~ 70°C)
Operating Humidity
10 ~ 90%
Power Supply
Input: AC 100 ~ 240V, 50/60Hz
Output: DC 24V, 5A
Power Consumption
76.5W (max)
USB-C Charging Power
Delivery
60W (max)
Product Dimensions
10.4” (265mm) x 5.9” (150mm) x
1.3” (32mm)
6.8” (173mm) x 3.7” (95mm) x
0.96” (24.5mm)
Product Weight
2.25lbs. (1020g)
0.9lbs. (410g)

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3. Panel Description
3.1 Transmitter
3.1.1 Front Panel
No.
Name
Description
1
Power LED
1x green indicator light; light is always on when the switcher has power
and is working normally, and goes out when power is off
2
SELECT
1x white non-backlit button, 3x blue indicator lights
Press the button the change input source (HDMI or USB-C); press and
hold for at least 3 seconds to toggle auto-switching mode
The indicator light of the selected source will always be on
3
DISPLAY
1x white non-backlit button, 2x blue indicator lights
Press the button to send the DISPLAY ON/OFF CEC and RS232
commands to the TX and RX terminals switches
The indicator light for the display’s current state will always be on
4
BLACK SCREEN
1x white non-backlit button, 2x indicator lights
Press the button to temporarily suppress video output (shows a black
screen)
The indicator light for the video output’s current state will always be on
5
EDID
1x 4-pin DIP switch for EDID management
6
DEVICES
2x USB 3.0 for connecting a camera, microphone, or other equipment
7
ETHERNET
1x RJ45 used for network passthrough transmission via HDBaseT
8
FW
1x Micro-USB for MCU firmware upgrades
FW
EDID
ON
OFF 1
0
1 2 3 4
HDMI
USB-C AUTO
1 2
DEVICES
ON OFF
DISPLAY
ON OFF
BLACK SCREEN
SELECT
AUTO/3s
ETHERNET
1 2 3 4 5 6 7 8

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3.1.2 Rear Panel
No.
Name
Description
1
USB-C
1x USB-C 3.0 input; supports 60W charging for connected devices
2
HOST
1x USB 3.0 port for connecting to HOST devices (such as a laptop)
3
HDMI IN
1x HDMI input for connecting to HOST devices (such as a laptop)
4
HDMI OUT
1x HDMI loop output
5
HDBASET
1x HDBaseT output
The green indicator light is always on when HDCP is detected, and
flashes when an input signal without HDCP is detected
The yellow indicator light is always on when the TX and RX are properly
connected
6
AUDIO OUT
1x 5-pin balanced stereo audio output for audio de-embedding
7
Grommet
GR1 corresponds to the USB-C input
GR2 corresponds to the HDMI input
SM: Switches to the corresponding video input source
BO: Temporarily suppresses video output (outputs a black screen) on
the corresponding video input source
8
RS232
LOCAL: For connecting control devices to control the transmitter
PASS: Bi-directional passthrough transmission via HDBaseT
9
Upgrade
1x Firmware Upgrade button
Press and hold for 3 seconds to enter Upgrade Mode, and the power
indicator will start flashing; users can then upgrade the unit’s
firmware via the RS232 port
Press again to exit Upgrade Mode
10
TCP/IP
1x RJ45 for TCP/IP control
11
DC 24V
Connect DC 24V, 5A power adapter
HDMI AUDIOHOST
L R
DC 24V
HDMI
USB-C TCP/IPHDBT
INPUT OUTPUT
RS232
Tx Rx
LOCAL
PASS
Tx Rx
SM BO
GR 1
GR 2
SM BO
60W
1 2 3 4 5 6 7 8 910 11

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3.2 Receiver
3.2.1 Front Panel
No.
Name
Description
1
OUTPUT
1x HDMI Output
1x 5-pin balanced stereo audio output for audio de-embedding
2
DEVICES
2x USB-A 2.0, 1x USB-C for connecting a keyboard, mouse, camera,
microphone, or other equipment
3.2.2 Rear Panel
No.
Name
Description
1
ETHERNET
1x RJ45 for network passthrough transmission via HDBaseT
2
HDBT IN
1x RJ45 HDBaseT input
The green indicator light is always on when HDCP is detected, and
flashes when an input signal without HDCP is detected
The yellow indicator light is always on when the TX and RX are properly
connected
3
RS232
1x 3-pin connector for RS232 passthrough transmission via HDBaseT
4
Power LED
1x green indicator light; always on when receiver has power and is
working normally
5
DC 24V
Connect DC 24V, 5A power adapter
DEVICES
21
4
3
HDMI AUDIOHDMI AUDIO
OUTPUT L R
1 2
RS232
Tx Rx
DC 24V
ETHERNET HDBT IN
1 2 3 4 5

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4. EDID Management
EDID settings for the switcher are controlled by the EDID DIP switches as
described below. In the following table, “0” indicates a switch in the Off or
Down position, while “1” indicates a switch in the ON or UP position.
DIP Switch Position
EDID Behavior
0000
Switcher will automatically read the EDID of the transmitter and receiver
HDMI outputs, and set its EDID to the lower of the two. If EDID cannot be
detected, the switcher will default to 1920x1080@60 8bit Stereo.
0001
1920x1080 @ 60Hz 8-bit High Definition Audio
0010
3840x2160 @ 60Hz Deep Color Stereo Audio
0011
3840x2160 @ 30Hz 8-bit Stereo Audio
0100
3840x2160 @ 30Hz Deep Color High Definition Audio
0101
3840x2160 @ 60Hz 4:2:0 Deep Color Stereo Audio
0110
3840x2160 @ 60Hz Deep Color High Definition Audio
0111
3840x2160 @ 60Hz Deep Color HDR LPCM 6CH
1011
Custom EDID1
1100
Custom EDID2
1101
Custom EDID3
1110
Custom EDID4
1111
EDID Management
FW
EDID
ON
OFF 1 0
1 2 3 4
HDMI
USB-C AUTO
1 2
DEVICES
ON OFF
DISPLAY
ON OFF
BLACK SCREEN
SELECT
AUTO/3s
ETHERNET
1 2 3 4 5 6 7 8

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5. GUI Control
The SCU21T-KVM can be controlled via TCP/IP protocols. The default IP settings are:
IP Address: 132.168.0.178
Subnet Mask: 255.255.255.0
Gateway: 192.168.0.1
Type the IP address of the switcher into a web browser on the control PC to open the web GUI login
page.
Username: admin
Password: admin
Enter the username and password, then click “Login” to open the web GUI.

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5.1 Video Tab
Select HDMI or USB-C as the active video input source, or toggle Auto-Switching mode
5.2 Configuration Tab
5.2.1 EDID
Choose the desired EDID format, or define a custom EDID setting

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5.2.2 Auto-Downscaling
Enable or disable automatic down-scaling for the transmitter and receiver video outputs
5.2.3 HDCP
Choose whether to have the HDCP for the transmitter and receiver follow the source or display

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5.2.4 Tags
Customize the tags for the HDMI and USB-C inputs, and for the transmitter and receiver HDMI
outputs

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5.3 CEC Tab
5.3.1 Input
Click to send the corresponding CEC command to the device connected to the HDMI input
5.3.2 Output
Click to send the corresponding CEC command to the device connected to either the transmitter or
receiver’s HDMI output

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5.3.3 User-Defined
Define custom CEC commands to send to either the transmitter or receiver’s HDMI inputs or outputs.
Click “Send” next to a custom command to send to the corresponding input or output
5.4 RS232 Tab
Choose whether to format RS232 commands as ASCII or HEX characters

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Baud Rate: 9600, 19200, 38400, 57600, 115200
Command Ending: NULL, CR, LF, or CR+LF
Command: Type an RS232 command to send to the third-party device connected to the RS232 port
5.5 Network Tab
Choose whether the switcher is set to a Static IP address or gets a DHCP automatically from the
network DHCP server
Set the IP Address, Subnet Mask, and Gateway of the switcher (only available when set to Static IP)

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5.6 Access Tab
Password: Modify the password for accessing the web GUI
Firmware Upgrade: Browse to the file location of the firmware upgrade file in the computer’s file
explorer. Press “Confirm” while the switcher is in Upgrade Mode to update its firmware.
Front Panel Lock: Lock or unlock the front panels buttons for controlling the switcher