StarTech ST121HDBT20L HDMI Over CAT6 Extender
overview
The StarTech ST121HDBT20L is a point-to-point HDMI extender kit (transmitter + receiver) designed to extend high-bandwidth HDMI 2.0 signals over Cat5e/Cat6 cabling for long-distance AV distribution. It supports 4K @ 60Hz up to 70 m (230 ft) and 1080p @ 60Hz up to 100 m (328 ft), maintaining signal integrity using visually lossless compression and 18 Gbps bandwidth.
It is deployed in digital signage, conference rooms, control rooms, and large facilities where HDMI cable length limitations prevent direct connections. The extender uses Power over Cable (PoC), allowing both units to operate with a single power adapter, simplifying installation and reducing infrastructure requirements.
The unit supports IR passthrough, enabling remote control of source devices from the display location. It is ideal for structured cabling environments leveraging existing CAT infrastructure. Do NOT use for multi-display distribution (matrix setups) or IP-based AV routing, as this is a dedicated point-to-point extender.
key features
- 4K @ 60 Hz up to 70 m over Cat6 cabling
- 1080p @ 60 Hz up to 100 m long-distance extension
- single cable with Power over Cable (PoC) support
- 18 Gbps bandwidth with 4:4:4 chroma sampling
- IR passthrough for remote source control


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