12G-SDI Cable: What It Is, Why It Matters, and How to Choose the Right Assembly
As 4K/Ultra HD becomes the baseline for broadcast, live events, OB vans, studios, and medical imaging systems, 12G-SDI has become one of the most efficient ways to move uncompressed video over coax. But hitting stable 12G performance is not only about the router or camera—it depends heavily on the cable quality, shielding, and termination.
In this article, we’ll explain what 12G-SDI is, typical applications, key cable/connector requirements, and how MOCO builds reliable 12G-SDI cable assemblies for OEM and system integrators.
What Is 12G-SDI?
12G-SDI (12-Gigabit Serial Digital Interface) is a professional video standard that carries uncompressed video over 75Ω coaxial cable at up to 12 Gb/s. Compared with 3G-SDI, 12G-SDI can transport higher-resolution signals (commonly 4K) through a single coax line, simplifying wiring and reducing converter needs in many setups.
Where 12G-SDI Cables Are Commonly Used
Broadcast & Studio: cameras, switchers, routers, monitors, recorders, and patch panels
Live Events & OB Vans: long cable runs, quick deployment, high reliability
Professional AV: 4K distribution in venues and high-end production facilities
Medical Imaging: operating room displays and imaging systems requiring stable video links
Industrial Vision: inspection systems and machine vision where robust connectors matter
What Makes a Good 12G-SDI Cable Assembly?
At 12G data rates, small details can cause big problems—signal reflections, higher attenuation, intermittent contact, or EMI pickup. A high-quality assembly typically focuses on four areas:
1) True 75Ω Impedance Control
12G-SDI systems depend on consistent impedance along the entire link: cable, connector, and termination geometry. Impedance mismatches can lead to reflections and eye-pattern collapse, especially on longer runs.
2) Low Loss Coax (Attenuation Matters)
Higher bandwidth means higher insertion loss per meter. Choosing the right coax construction and dielectric helps maintain signal margin for 12G. For long runs, low-loss cable selection becomes critical.
3) Strong Shielding for EMI/RFI
Live environments often include wireless systems, power distribution, and dense cabling. A good 12G-SDI cable uses robust shielding (foil + braid, or high-coverage braid) to minimize interference.
4) Reliable BNC Termination & Strain Relief
Even premium coax can fail if the connector is poorly terminated. Professional 12G assemblies require:
Proper crimp/compression or solder process (depending on connector style)
Controlled strip dimensions and clean conductor preparation
Strong strain relief and jacket retention to reduce pull damage
Consistent manufacturing to avoid intermittent contacts
How to Choose the Right 12G-SDI Cable for Your Setup
| Requirement | Recommended Focus |
|---|---|
| Short patch cables (rack / studio) | High-flex jacket, durable BNC, neat labeling, repeated mating reliability |
| Long runs (venue / OB / permanent install) | Low-loss coax selection, shielding performance, consistent impedance control |
| Frequent setup & teardown | Strain relief, abrasion resistance, reinforced connector back-end protection |
| High-EMI environments | Enhanced shielding design, better braid coverage, careful grounding/termination |
| OEM integration | Custom length, labels, packaging, batch control, test reports if required |
Tip: Cable performance is system-dependent. If you share your required length, device model, and usage scenario, MOCO can propose the best-fit coax and termination method.
MOCO 12G-SDI Cable Assembly Capabilities
MOCO provides custom cable assemblies for professional signal transmission applications, focusing on consistency, reliability, and scalable manufacturing. For 12G-SDI projects, we typically support:
Connector options: BNC to BNC, BNC to panel-mount solutions (based on project needs)
Custom lengths: from short patch cables to longer runs for installation projects
Manufacturing options: standardized work instructions, batch traceability support
Labeling & packaging: OEM label, barcode, and tailored packaging for shipment/warehouse
Quality control: process inspections and electrical continuity/assembly checks (per requirement)
If your project requires additional specifications (e.g., special jacket materials, higher flexibility, environmental resistance, or specific compliance documentation), MOCO can align the assembly plan with your product and market requirements.
Common Questions About 12G-SDI Cables
Can I use an old SDI coax cable for 12G-SDI?
Sometimes it may work for very short runs, but older cables/connectors may not maintain margin at 12G. For stable 4K transmission—especially at longer distances—use a cable assembly designed for 12G bandwidth and properly terminated 75Ω connectors.
Why does my 12G signal drop out intermittently?
Common causes include connector wear, weak strain relief, poor termination quality, tight bend radius, or EMI exposure. At 12G, small issues become visible quickly as dropouts or unstable images.
What information should I provide for a quotation?
For fast evaluation, share: required length, connector type (BNC/BNC or others), quantity, application scenario (studio/OB/install), and any labeling/packaging requirements.
Request a 12G-SDI Cable Assembly Quote
Need reliable 12G-SDI performance for 4K/Ultra HD? MOCO supports OEM/ODM cable assemblies with scalable production. Send us your requirements and we’ll recommend the right coax + termination solution.
Length: ____ m / ____ ft
Connector: BNC–BNC (or other)
Quantity: prototype / small batch / mass production
Use case: studio / live event / OB / medical imaging / industrial
