Tekvox SCU21T-KVM USB C Switcher and HD BaseT Receiver User Manual
- June 1, 2024
- TEKVOX
Table of Contents
SCU21T-KVM
79121-KVM User Manual
SCU21T-KVM
4K 2×1 HDMI/USB-C Switcher
& HDBaseT Receiver
All Rights Reserved
Version: 79121-KVM_2023V1.1
www.tekvox.com
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 February, 2023. 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.
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
Product Introduction
TEKVOX’s SCU21T-KVM is a 4K 2×1 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
Specifications
| Transmitter|
Receiver
---|---|---
Video
Inputs| lx HDMI (19-pin, Type-A, Female)
lx USB-C (Type-C, Female)| lx 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| lx HDMI (19-pin, Type-A, Female)
lx HDBaseT (RJ45, Female)| lx 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
Audio Output| lx Balanced Stereo (5-pin terminal block)| lx Balanced Stereo
(5-pin terminal block)
Audio Format| PCM 2.0
Frequency Response| 20Hz — 20kHz, ±3dB
Maximum Output Level| 0.88VRMS ±0.5dB
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
Crosstalk Isolation| < -80dB, 10kHz sine at OdBFS level (or max level before
clipping)
L-R Level Deviation| < 0.3dB, 1 kHz sine at OdBFS level (or max level before
clipping)
Output Load Capability| 1ka and higher (supports 10x parallel 10k0 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 (USB 2.0, 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%, non-condensing
Power Supply| Input: AC 100 ~ 240V, 50/60Hz
Output: DC 24V, 5A| 48V Power-over-Cable (PoC)
Transmission Distance| 328 feet (100m)
Bandwidth| 18Gbps
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)
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
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
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
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 1920×1080@60 8bit Stereo.
0001| 1920×1080 @ 60Hz 8-bit High Definition Audio
0010| 3840×2160 @ 60Hz Deep Color Stereo Audio
0011| 3840×2160 @ 30Hz 8-bit Stereo Audio
0100| 3840×2160 @ 30Hz Deep Color High Definition Audio
0101| 3840×2160 @ 60Hz 4:2:0 Deep Color Stereo Audio
0110| 3840×2160 @ 60Hz Deep Color High Definition Audio
0111| 3840×2160 @ 60Hz Deep Color HDR LPCM 6CH
1011| Custom EDID1
1100| Custom EDID2
1101| Custom EDID3
1110| Custom EDID4
1111| EDID Management
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.
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
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
5.2.4 Tags 
Customize the tags for the
HDMI and USB-C inputs, and for the transmitter and receiver HDMI outputs
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.
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
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)
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
RS232 Control
Before controlling the SCU21T-KVM, make sure that all relevant inputs and
outputs are connected, and that the COM port, baud rate, data bit, stop bit,
and parity bit are set correctly.
Baud Rate: 9600
Data Bit: 8
Stop Bit: 1
Parity Bit: None
6.1 System Control
All commands should be terminated with “
| Command | Description | Command & Feedback Example |
|---|---|---|
| PHDBTON. | Turn HDBaseT PoC On | HDBT 01 Power ON! |
| PHDBTOFF. | Turn HDBaseT PoC Off | HDBT 01 Power OFF! |
| HDMIA. | Set to Auto-Switching Mode | HDMI Out Switch Auto Mode! |
| HDMIM. | Set to Manual-Switching Mode | HDMI Out Switch Manual Mode! |
| HDMI [x]. | Select video input source |
x = 1 ~ 2
1 : USB-C Input
2 : HDMI Input| HDMI Out Switch to 01! HDMI Out Switch to 01!
POWON.| Turn switcher on| Power ON!
POWOFF.| Turn switcher off| Power OFF!
SIGNALTRG [x] MODE.| Set auto-switching detection method
x = 1 ~ 2
1 : 5V Detection
2 : TMDS Detection| Set Trigger Mode to 5V.
SIGNALTRGSTA.| Query the signal detection method (TMDS or 5V)| Get Trigger
Mode is 5V.
RST| Restore factory default settings| Factory Default!
Lock.| Lock front panel buttons| Front Panel Locked!
Unlock.| Unlock front panel buttons| Front Panel UnLock!
STA.| Query device status| SCU21T-KVM V1.0.0 PWON!
HDBT 01 Power ON!
HDMI Out 01 Down Scale OFF! HDMI Out 02 Down Scale OFF! HDMI Out Switch Auto
Mode! Get Trigger Mode is 5V. System Unlock!
Baudrate 9600! GUI_IP:192.168.0.200!
HDMI Out Switch 02!
Set Output Black Screen ON! IN 1 2
LINK Y Y OUT 1 2 LINK Y Y
Input 1 EDID From 1 User Define EDID!
Input 2 EDID From 1 Internal EDID! OUT 01 HDCP MAT DISPLAY!
OUT 02 HDCP MAT DISPLAY!
Set POFF Delay to 600 Second(s)!
RS232ONSAVE: [y]. [xxx]| Set an RS232 power on command to be sent to
the display when an input is detected
y = Baud Rate, 1 ~ 7
1 : 2400
2 : 4800
3 : 9600
4 : 19200
5 : 38400
6 : 57600
7 : 115200
[xxx] = RS232 command| Save PON Command:YYYYY,Baudrate is 9600!
RS232OFFSAVE:[y],[xxx].| Set an RS232 display off command to be sent when no
input is detected
y = Baud Rate, 1 ~ 7
1: 2400
2: 4800
3: 9600
4: 19200
5: 38400
6: 57600
7: 115200
[xxx] = RS232 command| Save POFF Command:TTTTTT,Baudrate is 9600!
RS232DLYOUT[xx]:[yy]| Set how long the switcher will wait before sending the
display power off command after no input is detected.
Default is 10 minutes (600s)
xx = 00
yy = seconds| Set POFF Delay To 10 Second(s)!
6.2 Source Control
| Command | Description | Command & Feedback Example |
|---|---|---|
| TVON. | Turn on display via CEC command | CEC_TC_POWON! |
CEC Output 01 Send Success. CEC Output 02 Send Success.
TVOFF.| Turn off display via CEC command| CEC_TV_POWOFF!
CEC Output 01 Send Success. CEC Output 02 Send Success.
TVVOL+.| Increase display volume via CEC command| CEC_TV_VOLUP!
CEC Output 01 Send Success. CEC Output 02 Send Success.
TVVOL-.| Decrease display volume via CEC command| CEC_TV_VOLDOWN!
CEC Output 01 Send Success. CEC Output 02 Send Success.
TVMUTE.| Mute display audio via CEC command| CEC_TC_VOLMUTE/UNMUTE!
CEC Output 01 Send Success. CEC Output 02 Send Success.
HDCP[x]PAS.| Set the output HDCP to follow the input x = 0 ~ 2
0: All outputs| OUT 01 HDCP PASSIVE! OUT 02 HDCP PASSIVE!
HDCP[x]MAT.| Set the output HDCP to follow the display
x = 0 ~ 2
0: All outputs| OUT 01 HDCP MAT Display! OUT 02 HDCP MAT Display!
HDCP[x]ON.| Forces HDCP1.4 open on the output
x = 0 ~ 2
0: All outputs| OUT 01 HDCP ON! OUT 02 HDCP ON!
HDCP[x]OFF.| Forces HDCP closed on the output
x = 0 ~ 2
0: All outputs| OUT 01 HDCP OFF! OUT 02 HDCP OFF!
DS[x]ON.| Enable downscaling on the HDMI output
x = 0 ~ 2
0: All outputs| HDMI OUT 01 Down Scale ON! HDMI OUT 02 Down Scale ON!
DS[x]OFF.| Disable downscaling on the HDMI output
x = 0 ~ 2
0: All outputs| HDMI OUT 01 Down Scale OFF! HDMI OUT 02 Down Scale OFF!
STA_IN.| Get source connection status| IN 1 2
LINK N N
/+[x]:yyy.| Send an RS232 command to control a connected third- party
device
x = Baud rate, 1 ~ 7
1: 2400
2: 4800
3: 9600
4: 19200
5: 38400
6: 57600
7: 115200
yyy = RS232 command| 123456
@OUT[xx].| Turn off the HDMI output’s 5V, making it undetectable as an
active source
x = Output port, 00 ~ 01 00: All outputs| Set Output Black Screen ON!
$OUT[xx].| Turn on the HDMI output’s 5V, making it detectable as an
active source
x = Output port, 00 ~ 01 00: All outputs| Set Output Black Screen OFF!
GETUIIP.| Get the web GUI IP address| GUI_IP:192.168.0.173!
SetGuiIP_DHCPON.| Set switcher to Dynamic IP address (DHCP)| GUI IP DHCP
ON!
SetGuiIP_DHCPOFF:
xxx.xxx.x.xxx.| Set switcher to static IP
address (default is 192.168.0.178)| GUI IP DHCP OFF!SETGUIIP:192.168.0.123!
EDIDUpgrade[xx].| Upgrades EDID data via serial port (requires
additional software)
xx = Input port, 00 ~ 02 x: All inputs Custom EDID is applied setting, but not
saved in switcher memoryOR
xx = User-defined EDID, U1 ~ U4
Only one user-defined EDID can be customized at once, and the switcher will
not automatically switch to the custom EDID after upgrading Ensure that all
HDBaseT is disconnected before sending command|
EDID/[xx]/[yy].| Set input port xx to use EDID setting yy
xx = 00 ~ 02
00: All input ports
yy = 01 ~ 12
01 ~ 08: Built-in EDID (cannot be changed)
09 ~ 12: User-defined EDID| Input 02 EDID Upgrade OK By 01 Internal EDID!
EDIDM[x]B[y].| Set input port y to inherit EDID from output x
x = 1 ~ 2
y = 0 ~ 2
0: All input ports| Input 01 EDID Upgrade OK By 02 EXT EDID!
**Baudrate[xx].| Set the RS232 baud rate to xx xx = 9600, 19200,
38400, 57600, or 115200| Set Local RS232 Baudrate Is 9600!
CEC[x][AA][BB] [CC][DD].**| Send custom CEC command x = Input or
output port, I or O AA = Port number, 01 ~ 02
FF: All ports
BB = Device Type (e.g. TV: 40/20/80, Blu-ray Player: 04/08, etc.)
CC = CEC Function Category
DD = CEC command to be sent (e.g. “41” for Volume +); can send up to 9
combined commands|
System Connection
Panel Drawing
