Coaxial cable is the round cable that runs from your cable box or DVR to the wall. It's used for cable TV, multimedia systems and high-speed Internet connections because the thick, plastic coating protects the audio-visual signal from being disrupted by other electronic noise. The most common reasons to splice coaxial cable are to shorten a cable that's too long or to extend a cable that's too short. In either case, cut and strip coaxial cable and splice it to another piece with a coaxial connector.
Measure out the length of cable you want to add to or subtract from your existing line. You'll need 1/2 to 1 inch of extra cable to add the connector, so factor that into your measurements.
Cut the cable using a coaxial cutter/stripper. A cutter/stripper has both a cable cutter and a stripper in one tool. Use a separate cutter and stripper if you don't have a combination tool on hand.
Insert the cable into the stripper and choose the "outer" setting. Put at least 1/2 inch of cable through the stripper, squeeze the clamp and twist the stripper to remove the outer layer of insulation.
Switch to the "inner" setting and insert about 1/4 inch of cable into the stripper. Clamp and twist again to strip off the silver inner layer. You're left with about 1/4 inch of bare copper center, then 1/4 inch of silver inner layer, then the outer insulation layer.
Pull back the outer strands of the braided silver inner layer. Fold them back over the black insulation. These strands will sit between the plastic insulation and the F connector.
Slide an F connector over the stripped end of cable until it covers the insulation. The copper cable center will stick out through the center hole of the connector.
Crimp the connector onto the wire using the upper end of the cutter/stripper or a coaxial cable crimp tool.
Repeat this process on the other cable end you want to splice. When the second connector is crimped, connect the cables to each other with a BNC coaxial adapter. A coaxial adapter looks like a small screw with threads on both ends.
Strip and connect as many cable ends as needed to create the final cable length you want.
- There are several types of coaxial F connectors. Ideal Industries, a multimedia installation provider, recommends Compression or Push-On connectors for a professional quality connection. Crimp-On and Twist-On connectors also provide very high-quality connections.
- Don't use regular scissors to cut coaxial cable. Although strong scissors will cut through the cable, they're not as sharp as a cable cutter. Regular scissors could splay the end of the copper cable center, possibly leading to signal loss.
Items you will need
- Coaxial cable cutter/stripper
- F-Connectors (2 or more)
- BNC coaxial adapter
- Coaxial cable crimp tool (optional)
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