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StarTech 4K HDMI Extender with Compact Transmitter - HDMI Over CAT5 - HDBaseT - UHD 4K - TAA (ST121HDBTDK)
- Simple and versatile installation with a compact, USB-powered transmitter that features a built-in HDMI cable
- Astonishing picture quality with support for UHD resolutions up to 4K
- Easy integration with existing CAT5/CAT6/CAT7 infrastructure
- Mounting hardware included
- 7.1 audio support
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Overview
Specs
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This 4K HDMI extender uses HDBaseT to transmit your HDMI A/V signal to a remote location up to 70 m (230 ft. ) away. Easy and Discreet Installation The transmitter in this HDMI HDBaseT extender kit features a small footprint and built-in HDMI cable that connects directly to your source for reduced clutter. It's powered from a USB port on your source device, which makes it easier to install in areas where power outlets may be limited. Mounting hardware is included for the receiver for a discreet, professional installation. Get 4K Video at 130 ft.
(40 m) This HDMI over CAT6 extender maintains your UHD 4K picture quality, even at 130 feet away from your video source. Because the extender is backward compatible with 1080p and lower resolutions at 230 feet away, you can comfortably use this extender to make any video source look great. The extender also supports 7.1 audio to ensure all audio channels are captured. Seamless Integration with Your Existing Infrastructure The kit extends HDMI over a single cable, unlike some HDMI extenders that require two cables, reducing potential failure points and lowering your cabling costs.
Ideal for digital signage, the HDMI over CAT6 extender uses standard CAT5e, CAT6 or CAT7 cables to extend HDMI video over the Ethernet infrastructure that's already in your building. The ST121HDBTDK is backed by a StarTech. com 2-year warranty and free lifetime technical support. More from the
Manufacturer Package Contents: 1 x HDBaseT Ttransmitter 1 x HDBaseT Receiver 1 x USB Power Cable (Transmitter) 1 x Universal Power Adapter (Receiver) (NA / EU / UK / AU) 1 x Mounting Kit (Receiver) 1 x Screw Kit for Mounting 1 x Footpad Set (Receiver) 1 x Quick Start
Guide Product Type: Video Extender Transmitter/Receiver
Product Type: Video Extender Transmitter/Receiver
Manufacturer Part Number: ST121HDBTDK
Limited Warranty: 2 Year
Connectivity Technology: Wired
Connectivity Technology: Wired
Manufacturer: StarTech.
com Product Name: HDBaseT Extender Kit with Compact Transmitter - HDMI over CAT5 - Up to 4K
Brand Name: StarTech.
com Brand Name: StarTech.
com Country of Origin: Taiwan
Maximum Operating Distance: 229.66 ft Number of
Network (RJ-45) Ports: 2 Number of
HDMI Inputs: 1
Media Type Supported: Twisted Pair Number of
Output Devices Supported: 1 Number of
Input Devices Supported: 1
TAA Compliant: Yes
Graphics Modes: 4K
Environmentally Friendly: Yes Maximum
Video Resolution: 4096 x 2160 Twisted Pair
Cable Standard: Category 7
Maximum Operating Distance: 229.66 ft Number of
Network (RJ-45) Ports: 2
Network (RJ-45): Yes Number of
HDMI Inputs: 1 Number of
HDMI Outputs: 1
HDMI In: Yes
HDMI Out: Yes
Media Type Supported: Twisted Pair Number of
Output Devices Supported: 1 Number of
Input Devices Supported: 1
TAA Compliant: Yes Packaged
Quantity Condition: Kit
(40 m) This HDMI over CAT6 extender maintains your UHD 4K picture quality, even at 130 feet away from your video source. Because the extender is backward compatible with 1080p and lower resolutions at 230 feet away, you can comfortably use this extender to make any video source look great. The extender also supports 7.1 audio to ensure all audio channels are captured. Seamless Integration with Your Existing Infrastructure The kit extends HDMI over a single cable, unlike some HDMI extenders that require two cables, reducing potential failure points and lowering your cabling costs.
Ideal for digital signage, the HDMI over CAT6 extender uses standard CAT5e, CAT6 or CAT7 cables to extend HDMI video over the Ethernet infrastructure that's already in your building. The ST121HDBTDK is backed by a StarTech. com 2-year warranty and free lifetime technical support. More from the
Manufacturer Package Contents: 1 x HDBaseT Ttransmitter 1 x HDBaseT Receiver 1 x USB Power Cable (Transmitter) 1 x Universal Power Adapter (Receiver) (NA / EU / UK / AU) 1 x Mounting Kit (Receiver) 1 x Screw Kit for Mounting 1 x Footpad Set (Receiver) 1 x Quick Start
Guide Product Type: Video Extender Transmitter/Receiver
Product Type: Video Extender Transmitter/Receiver
Manufacturer Part Number: ST121HDBTDK
Limited Warranty: 2 Year
Connectivity Technology: Wired
Connectivity Technology: Wired
Manufacturer: StarTech.
com Product Name: HDBaseT Extender Kit with Compact Transmitter - HDMI over CAT5 - Up to 4K
Brand Name: StarTech.
com Brand Name: StarTech.
com Country of Origin: Taiwan
Maximum Operating Distance: 229.66 ft Number of
Network (RJ-45) Ports: 2 Number of
HDMI Inputs: 1
Media Type Supported: Twisted Pair Number of
Output Devices Supported: 1 Number of
Input Devices Supported: 1
TAA Compliant: Yes
Graphics Modes: 4K
Environmentally Friendly: Yes Maximum
Video Resolution: 4096 x 2160 Twisted Pair
Cable Standard: Category 7
Maximum Operating Distance: 229.66 ft Number of
Network (RJ-45) Ports: 2
Network (RJ-45): Yes Number of
HDMI Inputs: 1 Number of
HDMI Outputs: 1
HDMI In: Yes
HDMI Out: Yes
Media Type Supported: Twisted Pair Number of
Output Devices Supported: 1 Number of
Input Devices Supported: 1
TAA Compliant: Yes Packaged
Quantity Condition: Kit
Warranty & Returns
Warranty, Returns, And Additional Information
Warranty
- Limited Warranty period (parts): 2 years
- Limited Warranty period (labor): 2 years
- Read full details
Return Policies
- Return for refund until: January 31, 2027
- Return for replacement until: January 31, 2027
- This item is covered by Newegg.com's Extended Holiday Return Policy.
- Read full return policy for details.
We want to ensure your holiday shopping this year is hassle-free. That’s why we’re automatically extending our return policies on almost every product! For purchases placed between November 1st, 2026 and December 31, 2026 you will have until January 31, 2027 to return your product.
Manufacturer Contact Info
- Manufacturer Product Page
- Manufacturer Website
- Support Phone: 1-800-265-1844
- Support Email: support@startech.com
- Support Website
- View other products from STARTECH
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The StarTech ST121HDBTDK is an HDBaseT HDMI extender kit for sending video and 7.1-channel audio over a single Cat5e-or-better cable, making it suitable for classrooms, meeting rooms, and digital-signage installations that need a display up to 230 ft. away; it supports 4K up to 130 ft. and 1080p up to 230 ft.
Recommended For
- Meeting-room and classroom AV installers who need to connect an HDMI source to a projector across a dedicated Cat5e-or-better cable run, rather than routing a long HDMI cable.
- Facilities teams setting up fixed digital-signage displays across a building where a direct Cat5e, Cat6, or Cat7 cable can connect the source to a remote screen.
- AV installers who want a small transmitter at the source end: its built-in HDMI cable connects directly to the source, and USB power can help where a nearby outlet is limited.
- Users extending a 1080p source to a remote TV, monitor, or projector over a dedicated cable run of up to 230 ft., or a 4K source over a shorter run of up to 130 ft.
Spec Summary
| Attribute | Value |
|---|---|
| Best For | Extending HDMI video from a source such as a Blu-ray player or computer to a TV, monitor, or projector over Cat 5e UTP or better cabling, with support for 4K at shorter distances and 1080p up to 230 ft |
| Video Extension Performance | HDBaseT extension over a single cable up to 70 m (230 ft); maximum resolution is 4096 × 2160 at 30 Hz, with 4K supported up to 130 ft and 1080p up to 230 ft; widescreen supported |
| Connections And Interfaces | HDMI input and RJ-45 output on the local transmitter; HDMI output and RJ-45 input on the remote receiver; HDMI video output signal |
| Audio Support | Supports 7.1 surround sound |
| Power | USB-powered transmitter; receiver uses the included adapter with 100–240 V AC input and 12 V DC, 1.5 A output; positive center-tip polarity, M plug type |
| Mounting And Included Items | Rack-mountable; package includes transmitter, receiver, 1310 mm USB power cable, universal receiver power adapter, receiver mounting kit, screw kit, footpads, and quick start guide |
| Physical Specifications | Approximately 0.98 × 2.68 × 3.15 in and 8.89 oz |
| Operating Environment | Operating temperature: 0°C to 40°C; storage temperature: −10°C to 60°C; humidity: 0% to 80% RH, non-condensing |
| Model Identifiers | StarTech.com ST121HDBTDK |