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Pair of compact aluminium boxes with HDMI and RJ45 ports, plus power adapter and mounting brackets

STARTECH

STARTECH ST121HDBT20L HDMI over CAT6 extender 100m 4K60Hz

SKU CH-0MYC-BXYZ3 MPN ST121HDBT20L

Extends HDMI over a single CAT5e or CAT6 cable with 4K60Hz up to 70m and 1080p60 up to 100m, plus 7.1 audio and power over cable

  • HousingAluminum
  • Resolution Support3840x2160 (4K) @ 60 Hz 2560x1600 1920x1200 @ 60 Hz 1920x1080
  • Audio7.1 Surround Sound
  • HDMILocal Unit: 1 x HDMI (19-pin) Female Input Remote Unit: 1 x
  • Network InterfaceLocal Unit: 1 x RJ-45 Female Output Remote Unit: 1 x RJ-45 F
  • LED Indicator1 x status LED (local) 1 x status LED (remote)
  • 4K60Hz UHD video up to 70m over single CAT5e cable
  • 1080p60 signal reaches 100m using existing network cabling
  • Power over cable removes need for separate receiver supply
  • Aluminium housing with mounting brackets enables tidy professional installs
  • 1 surround sound passes through with IR control included

Extender for 4K60 HDMI over CAT6

The StarTech ST121HDBT20L transmits HDMI signals up to 100 metres over a single CAT5e or CAT6 cable. It supports 3840x2160 at 60 Hz to 70 metres and 1080p at 60 Hz to the full 100 metres. The aluminium transmitter and receiver each measure 1.00 by 3.00 by 4.00 inches and weigh 0.24 lb. Installers and AV integrators use it to bridge projectors, displays or matrices across rooms or floors.

Power-over-cable kit with IR and mounts

A universal AC adapter powers the local unit; the remote unit draws power over the same CAT cable, so no outlet is needed at the display. The box includes an IR blaster, IR receiver, two mounting brackets and eight rubber feet for fixed or surface mounting. A status LED on each unit confirms link and signal integrity. Setup requires no software or configuration.

70-metre 4K60 headroom, 100-metre 1080p limit

At 70 metres the extender carries full 4096x2160 60 Hz with 7.1 surround audio. Beyond that distance it falls back to 1920x1080 60 Hz up to the 100-metre maximum. It does not support HDR metadata, HDCP 2.3 or resolutions above 4K60. Buyers needing 4K60 past 70 metres or 8K transport should consider fibre-based solutions.

Highlights

  • 4K60Hz UHD video up to 70m over single CAT5e cable
  • 1080p60 signal reaches 100m using existing network cabling
  • Power over cable removes need for separate receiver supply
  • Aluminium housing with mounting brackets enables tidy professional installs
  • 1 surround sound passes through with IR control included

Specifications

BrandStarTech.com
ModelST121HDBT20L
HousingAluminum
Resolution Support3840x2160 (4K) @ 60 Hz
2560x1600
1920x1200 @ 60 Hz
1920x1080 (1080p)
1280x720 (720p)
Audio7.1 Surround Sound
HDMILocal Unit: 1 x HDMI (19-pin) Female Input
Remote Unit: 1 x HDMI (19-pin) Female Output
Network InterfaceLocal Unit: 1 x RJ-45 Female Output
Remote Unit: 1 x RJ-45 Female Input
LED Indicator1 x status LED (local)
1 x status LED (remote)
Power Consumption18W
Power SupplyCenter Tip Polarity: Positive
Input Current: 0.6A
Input Voltage: 100 ~ 240V AC
Output Current: 1A
Output Voltage: 18V DC
Plug Type: M
Power Source: AC Adapter Included
SpecificationHardware:
Audio: Yes
Cabling: Cat 5e UTP or better
Ports: 1
Performance:
Max Distance: 330 ft.
Maximum Cable Length: 328.4 ft.
Maximum Digital Resolutions:
Up to 70m: 4096 x 2160 (4K) @ 60 Hz
Up to 100m: 1080p @ 60 Hz
Wide Screen Supported: Yes
Environmental
Humidity: 0% - 80% RH (non-condensing)
Operating Temperature: 0 to 40 celsius degree
Storage Temperature: -10 to 60 celsius degree
Physical Characteristics:
Color: Black
FeatureGet astonishing video quality at impressive distances with UHD 4K 60 Hz resolution at up to 70m (230 ft.) and 1080p 60 Hz resolutions at up to 100m (330 ft.)
Hassle-free setup with video and power over a single CAT5e or CAT6 cable
Sleek professional installation with optional mounting hardware included
Remotely control your video source from the location of your remote display, with support for IR extension
Dimensions1.00" x 3.00" x 4.00"
Weight0.24 lb.
Package Content1 x HDMI over CAT6 transmitter
1 x HDMI over CAT6 receiver
1 x universal power adapter (NA/JP, EU, UK, ANZ)
1 x IR blaster
1 x IR receiver
2 x mounting brackets
8 x rubber feet
1 x quick-start guide
Shipping weight0.23 kg
Package size280 × 206 × 62 mm

Questions about this item

Will the power adapter need replacing after long-term use?

The included universal AC adapter supplies 18 V DC at 1 A and is rated for 100–240 V AC input, so it can be swapped with any matching 18 V DC 1 A supply if it ever fails.

At what distance does the 4K 60 Hz signal drop to 1080p?

4K 60 Hz is supported up to 70 m (230 ft); beyond that, up to 100 m (330 ft), the maximum resolution falls to 1080p 60 Hz.

How much heat or noise does the extender produce when running continuously?

The aluminium-housed units draw 18 W total with no fans, so they run silently and generate only modest warmth during all-day operation.

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