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How-to · UK domestic

How to fit a TV aerial coaxial cable connector

Fitting a Belling-Lee aerial plug or adding a new TV wall socket is a straightforward job once you know how to strip the cable correctly and which connector type matches your aerial system. Get the braid or core wrong and you get no picture or terrible interference.

Helpful video reference. We use John Ward's (jwflame) "Coaxial Cables for TV, RG6, Connectors Twist, Crimp, Compression, Belling Lee Plug" as the video reference here. John covers the UK-specific cable types and connector standards, the differences between twist-on, crimp and compression methods, and the Belling-Lee plug that is standard on every UK terrestrial aerial socket.

Before you start. Fitting coaxial aerial cable and connectors is not notifiable work under Part P. However, if you are chasing a new cable run into walls or running armoured cable to an outbuilding aerial point, the cable route and any new consumer unit connections do fall under Part P. This guide covers the connector and socket end of the job only. Any mains wiring nearby must be isolated at the consumer unit before you drill or chase.

1. Choose the right coaxial cable

UK terrestrial TV aerial systems use CT100, widely sold as WF100. It has a foam dielectric (the insulating core between the centre conductor and the braid) and a foil-plus-braid screen that provides good rejection of FM radio interference. The impedance is 75 ohms, matching every UK aerial amplifier and splitter.

Satellite dish systems use RG6 quad-shield, which has much better high-frequency screening. The two cable types look similar but they are not interchangeable in a satellite run: CT100 cannot carry the signal power from a satellite LNB without excessive loss.

For running cable inside walls or in surface trunking, standard CT100 is fine. For outdoor runs exposed to UV, use a UV-rated version with a black outer sheath.

2. Choose the right connector type

UK terrestrial aerial sockets and TV inputs use the Belling-Lee connector, formally standardised as IEC 61169-2. It is the plug with a centre metal pin that pushes into the socket. This is what goes on the end of your aerial cable to connect to the TV or to a wall plate socket.

Satellite and cable TV systems use F-type connectors, which screw on. The two are physically different and not interchangeable. If you are adding a point that could be used for either, fit a diplexer wall plate that accepts both an aerial and a satellite feed.

3. Choose your fitting method

4. Strip the cable

A coaxial cable stripper makes this much easier and avoids nicking the braid or foil. If using a craft knife, work carefully and do not cut into the copper braid.

Remove 25 mm of outer sheath to expose the braided copper screen. Fold the braid back carefully over the outer sheath, away from the cable end. Remove the foil layer that sits between the braid and the dielectric. Strip the inner dielectric to expose around 8 mm of copper centre core. The exact lengths depend on the connector manufacturer: check the instructions supplied with your specific connector.

The most common errors are cutting through strands of the braid (which reduces screening) and leaving the braid and centre core so close they are at risk of touching (which kills the signal entirely).

5. Fit the connector

For a standard Belling-Lee plug: slide the metal body over the cable, centre the copper pin through the hollow connector pin, fold the braid under the metal clamping ring and tighten the grub screw or roll the clamping ring down. Tug the connector gently to confirm it is mechanically secure.

For crimp types: slide the ferrule onto the cable first, then the connector body, then crimp with the tool. The ferrule compresses the outer sheath against the braid clamp inside the connector. For compression types: follow the specific sequence in the manufacturer's instructions, since the assembly order matters.

6. Fit the wall plate socket

Coaxial wall plates fit a standard UK single-gang back box, either 25 mm or 35 mm deep. The back of the socket has a connection for the centre core and a clamp or screw for the braid. Strip the cable end as above, push the centre core into the pin contact, fold the braid under the braid clamp, and tighten. Neither conductor must touch the other or the back box metalwork.

Before fitting the faceplate, connect a TV or aerial signal meter to the socket and check for a signal. A good signal is far easier to trace at the open back box than after the faceplate is fitted.

Poor or no picture after fitting: first check neither conductor is shorted to the other at the connector you just made. Then check the aerial itself has a clear line of sight and is correctly aligned. If signal is weak at every socket, an aerial amplifier or a head-end distribution amplifier may be needed. Do not stack amplifiers: this typically makes things worse.

When to call us

If you need a new socket run chased into a wall, or if the aerial system is connected to a consumer unit isolation switch or mains distribution amplifier, that part of the job may need an electrician. Richard can also trace signal distribution faults in older properties where the aerial wiring layout has been lost.

Need a new TV point in east Kent?

Richard can advise on aerial points, signal distribution and any mains-side work the installation requires, on small local jobs at the £10 per 10-minute rate.

Contact Richard

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