How to correctly choose and configure an HDMI splitter to split the signal to several screens without loss of quality.
Why does a regular HDMI splitter not work? The fight against a black screen and HDCP
{author=2}Connecting a video source to two receivers using the cheapest passive three-way adapter usually ends with a black screen, flickering, or an HDCP error. An HDMI signal is not a traditional analog signal, but a digital, bidirectional protocol that requires constant authorization and parameter negotiation between devices.
The correct solution is an active HDMI splitter. This device manages HDCP encryption keys and EDID (Extended Display Identification Data) profiles, ensuring stable image transmission to each display without loss of quality.
HDMI splitter vs HDMI switch – the key difference
The difference between a splitter and a switch comes down to the direction of signal transmission:
- Switch: Allows you to connect several sources (e.g. a console, decoder, PC) to one receiver (TV, projector) and switch between them.
- Splitter: Takes the signal from one source and duplicates it simultaneously on several screens.
Important note about computers: An HDMI splitter is used only for image cloning (Mirroring). Due to the lack of support for MST (Multi-Stream Transport) technology in the HDMI standard, a splitter does not allow you to extend the desktop onto two independent monitors. To extend the workspace, DisplayPort technology or an external USB graphics card (e.g. DisplayLink) is required.
Key technical parameters – what determines signal stability?
The basis for stable operation of an AV installation is the use of a splitter with an external power supply (e.g. 5V). Passive splitters draw power directly from the source's HDMI connector. This current is too weak to power the integrated circuit and transmit the signal over longer distances, which results in random image dropouts (so-called HDMI handshake dropouts).
An active splitter amplifies the signal while maintaining bandwidth up to 18 Gbps (for HDMI 2.0). This allows smooth 4K HDR transmission without interference or slowdowns.
Beware of passive splitters!
Using passive adapters without external power supply and galvanic isolation creates a risk of damaging HDMI ports due to ground potential differences. In addition, the lack of HDCP support prevents playback of content from VOD services (Netflix, HBO, Disney+).
Understanding EDID and HDCP – the key to a trouble-free installation
EDID (Extended Display Identification Data) is a set of resolution and audio information sent by the screen to the source. When you connect a 4K TV and a Full HD monitor, a simple splitter will force the lower 1080p resolution on both devices. Advanced 4K splitters have a built-in downscaler or EDID switches, which allows a 4K signal to be sent to the newer screen while simultaneously scaling it down to 1080p for the second receiver.
HDCP (High-bandwidth Digital Content Protection) protects digital content against copying. Modern sources (PS5, 4K decoders, Smart TV) require compatibility with the HDCP 2.2 standard. The selected splitter must support conversion of HDCP 2.2 keys to HDCP 1.4 to avoid a black screen when playing protected materials.
Long distances – Splitter Extenders over twisted pair cable
Copper HDMI cables above 10–15 meters lose transmission stability. For longer distances (30–50 m), a splitter-extender over Cat6/Cat7 twisted pair cable is used. The HDMI signal from the transmitter is sent via network cable to receivers (Rx) placed near the screens.
The advantages of this solution are:
- PoC (Power over Cable) technology: Receivers near the screens do not require separate power supplies.
- Loop output (HDMI Loop Out): Allows connection of a local preview monitor near the signal source.
- Ease of installation: Computer twisted pair cable is easier to pull through conduits than a rigid HDMI cable.
- Disconnect power from 230V sockets: Connecting HDMI cables while powered on risks damaging transmission circuits due to electrostatic discharge (ESD).
- Prepare the cabling: For distances above 15 m, use Cat6/Cat6a twisted pair cable or HDMI AOC optical cables. Route the cables away from 230V installations.
- Connect the devices: Connect the source to the HDMI Input port, and the receivers to the HDMI Output ports (or the RJ45 outputs of the extenders).
- Set the EDID switches: For screens with different resolutions, enable Auto/Mixed mode or activate the downscaling function.
- Startup sequence (Handshake): Turn on the power in the following sequence: first the HDMI splitter, then the TVs/monitors, and finally the signal source (decoder/console).
Specialist installation splitters at DMTrade
Signal splitting is also used in other low-voltage and telecommunications installations:
- GSM/LTE/5G splitters (e.g. Poynting SMA): Split the signal from one external antenna to two modems or routers with minimal wave attenuation.
- Starlink Mini PoE splitters (SSA15): Enable power supply and data transmission in mobile Starlink terminals directly via Ethernet twisted pair cable (PoE), eliminating unnecessary power supplies in car or yacht installations.
| Splitter type | Medium and connectors | Application | Main advantages |
|---|---|---|---|
| HDMI 4K Splitter Extender (2x6) | HDMI / RJ45 (Cat6/7) | Signal distribution from 2 sources to 6 screens (up to 50 m) | 4K support, integrated transmission over twisted pair cable, ideal for pubs and conference rooms. |
| Poynting SPLT-16-V1-02 SMA | GSM/LTE/5G (SMA connectors) | Splitting the antenna signal to 2 LTE/5G routers | Wide band (698-3800 MHz), low attenuation losses, high port isolation. |
| SBL 444 Blue Line 2-way | RTV/SAT (F connectors) | Signal branching in antenna paths and multiswitches | Full DC pass, solid die-cast housing. |
| Starlink Mini PoE Splitter SSA15 | PoE / RJ45 & DC | Power and data for Starlink Mini terminals | Cabling reduction, power over Ethernet in vehicles and boats. |
FAQ
Summary
Choosing an active signal splitter (with its own power supply and EDID/HDCP support) is the only way to eliminate problems with a black screen and loss of quality. For longer distances, Cat6 twisted pair transmission systems are indispensable. Check the full range of transmission devices and splitters in the DMTrade store.
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