StarTech.com ST121 Series User manual

Manual Revision: 04/16/2021
DE: Bedienungsanleitung - de.startech.com
FR: Guide de l'utilisateur - fr.startech.com
ES: Guía del usuario - es.startech.com
IT: Guida per l'uso - it.startech.com
NL: Gebruiksaanwijzing - nl.startech.com
PT: Guia do usuário - pt.startech.com
For the most up-to-date information, please visit: www.startech.com
ST121UTP / ST121UTPGB / ST121UTPEU
VGA over Cat5 Video Extender (ST121 Series)
*actualproduct may vary from photos

FCC Compliance Statement
This equipment 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 residential installation. 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.
However, there is no guarantee that interference will not occur in a particular installation. If
this equipment does cause harmful interference to radio or television reception, which can
be determined by turning the equipment o and on, the user is encouraged to try to correct
the interference by one or more of the following measures:
• Reorient or relocate the receiving antenna.
• Increase the separation between the equipment and receiver.
• Connect the equipment into an outlet on a circuit dierent from that to which the receiver
is connected.
• Consult the dealer or an experienced radio/TV technician for help.
Industry Canada Statement
This Class A digital apparatus complies with Canadian ICES-003.
Cet appareil numérique de la classe [A] est conforme à la norme NMB-003 du Canada.
CAN ICES-3 (A)/NMB-3(A)
This device complies with Industry Canada licence-exempt RSS standard(s). Operation is
subject to the following two conditions:
(1) This device may not cause interference, and (2) This device must accept any interference,
including interference that may cause undesired operation of the device.
Le présent appareil est conforme aux CNR d’Industrie Canada applicables aux appareils radio
exempts de licence.
L’exploitation est autorisée aux deux conditions suivantes:
(1) l’appareil ne doit pas produire de brouillage, et (2) l’utilisateur de l’appareil doit accepter
tout brouillage radioélectrique subi, même si le brouillage est susceptible d’en compromettre
le fonctionnement.
Use of Trademarks, Registered Trademarks, and other Protected Names and Symbols
This manual may make reference to trademarks, registered trademarks, and other protected
names and/or symbols of third-party companies not related in any way to StarTech.com.
Where they occur these references are for illustrative purposes only and do not represent an
endorsement of a product or service by StarTech.com, or an endorsement of the product(s)
to which this manual applies by the third-party company in question. Regardless of any
direct acknowledgement elsewhere in the body of this document, StarTech.com hereby
acknowledges that all trademarks, registered trademarks, service marks, and other protected
names and/or symbols contained in this manual and related documents are the property of
their respective holders.

Instruction Manual i
Table of Contents
Introduction ............................................................................................................. 1
Packaging Contents..........................................................................................................1
System requirements........................................................................................................2
Installation................................................................................................................ 1
Hardware Installation .......................................................................................................1
Local Unit..............................................................................................................................2
Remote Unit.........................................................................................................................2
Driver Installation...............................................................................................................4
Troubleshooting ...................................................................................................... 5
Wiring Diagram........................................................................................................6
Specications ...........................................................................................................7
Technical Support.................................................................................................... 8
Warranty Information............................................................................................. 8

Instruction Manual 1
Introduction
Packaging Contents
• 1 x VGA Video Extender Local Unit
• 1 x VGA Video Extender Remote Unit
• 1 x Mounting Bracket Kit
• 2 x Power Adapters
• 1 x Instruction Manual
System Requirements
• VGA enabled video source and display
• Available AC electrical outlet at local and remote locations
• VGA male/female cable to connect video source to extender
• VGA male/male cable(s) to connect display devices to extender
Installation
Hardware Installation
This product is composed of two dierent units: the Local Unit and the Remote Unit. The
Local Unit takes the output from a VGA signal source (usually a computer) and transmits
it to the Remote Unit over Category 5 Ethernet cable. The remote displays (monitor,
projector, etc) connect to the Remote Unit using standard VGA connections and displays
the image from the local computer onto the remote displays.

Instruction Manual 2
Local Unit
Remote Unit
Power
Connector
RJ45
output VGA input
(male)
VGA output
(female)
Power
Connector
RJ45
input
Signal Equalizer
switch
VGA output
(female)

Instruction Manual 3
Preparing Your Site
1. Determine where the local video source (i.e. computer) will be located and set up the
device.
2. Determine where the remote display will be located and place/mount the display
appropriately.
3. If you are using surface cabling, ensure you have enough Cat5 unshielded twisted pair
(UTP) Ethernet cabling to connect the Local Unit to the Remote Unit’s location, and
that each end is terminated with a RJ45 Ethernet connector. The cabling should not go
through any networking equipment (i.e. router, switch).
OR
If you are using premise cabling, ensure that the Cat5 unshielded twisted pair (UTP)
Ethernet Cabling between the Local Unit and the Remote Unit has been properly
terminated in a wall outlet in each location and there is a patch cable long enough to
connect the Remote Unit and the Local Unit to their respective outlets. The cabling
should not go through any networking equipment (i.e. router, switch).
Installing the Local Unit
1. Place the Local Unit near the local (source) computer.
2. Switch o the computer and disconnect any existing VGA cables.
3. If desired, connect the VGA cable from the local computer display(s) to the“Monitor”
ports on the Local Unit. This will enable you to see video locally while an image is
transmitted to the remote display. You may choose to connect up to two local displays,
one for each“Monitor”port. Both outputs display the same image.
4. Connect a male-to-female DE-15 VGA cable (not provided) to the VGA Output on the
local computer. Connect the opposite end to the VGA IN port on the Local Unit.
5. Connect the Cat5 cable connection to the “CAT5 OUT”on the Local Unit.
6. Connect the Power Adapter (provided) into an appropriate power source and plug the
opposite end into the power connector on the Local Unit. The POWER LED will light up.

Instruction Manual 4
Installing the Remote Unit
1. Connect the Remote Unit to the Cat5 cable connection from the Local Unit, to the
“CAT5 IN” port.
2. Connect the VGA cable from the remote display(s) to the opposite side of the Remote
Unit, marked “Monitor”. You may choose to have either one or two displays at the
remote location connected to the Remote Unit. Both outputs display the same image.
3. Connect the Power Adapter (provided) into an appropriate power source and plug the
opposite end into the power connector on the Remote Unit. The POWER LED will light
up.
CAUTION: The Category 5 Ethernet cables that connect the Local and Remote Units
carry electrical current and should not be plugged in to other devices, as they may
cause damage. We strongly recommend marking the Ethernet cables you are using
with this product at both locations for easy identication.
OPTIONAL: with the optional mounting brackets (StarTech.com ID: ST121MOUNT),
any ST121 series Remote Unit can be securely mounted to a wall or other surface.
Completing the Installation
1. Switch on the local computer and local display(s) (if used).
2. Switch on the display(s) at the remote location.
3. Verify that the remote display is properly displaying the image from the local
computer connected to the Local Unit.
4. Use the Signal Equalizer to improve the image on the remote display(s) based on the
approximate length of Ethernet cable between the Local and Remote Units.
Driver Installation
No driver installation is required for this video extender as it is an external hardware only
solution, invisible to the computer system.

Instruction Manual 5
Troubleshooting
The following section provides troubleshooting help. The solutions are arranged in the
order they should be attempted in most situations. If you continue to have diculties
after attempting the solutions in this section, please contact StarTech.com technical
support.
Symptom: The remote displays are black or display a “no signal” message.
Cause: The Remote Unit is not receiving a signal from the Local Unit.
Remedy:
1. Check that the display is receiving power and that all cables are connected.
2. Check that the display is connected to the Remote Unit.
Symptom: The remote displays do not display an image when the local computer wakes
up from Standby Mode.
Remedy: Power the remote displays OFF and ON again.
Symptom: One or more remote displays is distorted, noisy, or displays a “signal error” or
similar error message.
Cause: The screen resolution and/or refresh rate on the local computer may be set too
high for the capabilities of the remote display.
Remedy:
1. Adjust the local computer to a lower resolution and refresh rate until the remote
display shows an image.
2. Gradually increase the resolution and refresh rate on the local computer until the
remote displays ceases to display an image.
3. Return the resolution and refresh rate on the local computer to the highest
resolution and refresh rate setting that displayed an image on the remote display.
4. Adjust the Signal Equalizer on the Remote Unit for best performance.
NOTE: If you are still unable to see an image at the remote location after trying the above
solutions, it is recommended that you verify the Ethernet cable installation to the remote
display before calling technical support. This can be used using a standard cable tester. If
you do not have a cable tester, contact a local computer service or wiring professional.

Instruction Manual 6
Pin Wire Color Pair
1 White/Orage 2
2 Orange 2
3 White/Green 3
4 Blue 1
5 White/Blue 1
6 Green 3
7 White/Brown 4
8 Brown 4
Wiring Diagram

Instruction Manual 7
Specications
Connectors (Local)
1 x DE-15 VGA male
1 x DE-15 VGA female
1 x RJ45 Ethernet female
1 x Power Connector
Connectors (Remote)
2 x DE-15 VGA female
1 x RJ45 Ethernet female
1 x Power Connector
LEDs (per unit) 1 x Power, 1 x Activity
Maximum Cable Distance 150m (500 ft) @ 1024x768
Maximum Video Resolution 1440x900 @ 50m (150 ft)
Power Adapter 12VDC, 1.5 A, center positive
Dimensions (LxWxH) 60.0mm x 83.0mm x 20.0mm
Weight 181g

Instruction Manual 8
Technical Support
StarTech.com’s lifetime technical support is an integral part of our commitment to provide
industry-leading solutions. If you ever need help with your product, visit www.startech.
com/support and access our comprehensive selection of online tools, documentation, and
downloads.
For the latest drivers/software, please visit www.startech.com/downloads
Warranty Information
This product is backed by a two year warranty.
In addition, StarTech.com warrants its products against defects in materials and
workmanship for the periods noted, following the initial date of purchase. During this
period, the products may be returned for repair, or replacement with equivalent products
at our discretion. The warranty covers parts and labor costs only. StarTech.com does not
warrant its products from defects or damages arising from misuse, abuse, alteration, or
normal wear and tear.
Limitation of Liability
In no event shall the liability of StarTech.com Ltd. and StarTech.com USA LLP (or their
ocers, directors, employees or agents) for any damages (whether direct or indirect,
special, punitive, incidental, consequential, or otherwise), loss of prots, loss of business, or
any pecuniary loss, arising out of or related to the use of the product exceed the actual price
paid for the product. Some states do not allow the exclusion or limitation of incidental or
consequential damages. If such laws apply, the limitations or exclusions contained in this
statement may not apply to you.

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