Every SDI cable ends with a BNC connector. But not all BNC connectors are created equal. The termination method—how the connector attaches to the cable—affects durability, signal quality, and serviceability.
Here's what you need to know about the three main types: crimp, compression, and solder.
Crimp Connectors
Crimp connectors use a specialized tool to mechanically squeeze the connector onto the cable. The crimp creates a permanent bond between connector and cable jacket.
The good: Fast to install with the right tools. Consistent results once you've mastered the technique. Good for high-volume cable making. Lower cost per connector.
The reality: Requires a quality crimp tool—cheap tools create inconsistent connections. Different cable diameters need different die sizes. The crimp is permanent; if you mess up, you cut it off and start over.
Best for: Production environments making many cables, rental houses, situations where speed matters and you have proper tools.
Compression Connectors
Compression connectors use a compression tool to force an internal sleeve against the cable, creating a watertight seal. These have become increasingly popular for professional applications.
The good: Excellent strain relief. Weather-resistant seal. More forgiving of slight cable diameter variations. Very consistent connections.
The reality: Higher cost per connector than crimp. Still requires a dedicated compression tool. Once compressed, they're permanent like crimps.
Best for: Outdoor and harsh environment use, permanent installations, situations where weather sealing matters.
Solder Connectors
Solder connectors require manually soldering the center conductor to the connector pin. This is the traditional method and still used for high-end applications.
The good: Maximum control over the connection quality. Can achieve excellent electrical performance. Repairable—you can reheat and redo. No special crimping tools required.
The reality: Requires soldering skill and practice. Much slower than crimp or compression. Heat can damage the dielectric if you're not careful. Quality varies with the person doing the work.
Best for: Custom one-off cables, repair situations, applications where you need maximum control over the connection.
What About Pre-Made Cables?
When you buy quality pre-made cables, you're typically getting machine-crimped or compression-fitted connectors made in controlled conditions. This consistency is actually an advantage—factory termination with proper tooling often beats field termination.
The question isn't which termination method is "best." It's which method was done correctly, with proper tools, by someone who knows what they're doing.
How to Spot Quality Termination
Regardless of method, quality termination shows these signs:
The connector sits straight on the cable with no visible gap or angle. The center pin is centered and not bent. The cable jacket shows no crushing or deformation. The BNC locking mechanism operates smoothly.
Bad termination shows obvious problems: crooked connectors, visible gaps, crushed jackets, center pins that wobble. These cables will fail—it's just a matter of when.
The Bottom Line
For most working camera operators, pre-made cables with quality factory termination are the practical choice. You get consistent results without needing to invest in tools or develop termination skills.
If you're making your own cables, match your termination method to your situation: crimp for volume, compression for harsh environments, solder for custom work and repairs.
What matters most isn't the termination type—it's that the termination was done correctly. A perfect solder joint beats a sloppy crimp every time, and a proper crimp beats a cold solder joint.
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