I have a chimney aerial which we use to get terrestrial TV (Freeview). The cable on the outside wall has been cut accidentally - is it possible to join the two ends somehow? Luckily an indoor setup seems to work OK (electrically powered wall-mounted aerial) but I'd like to revive the outdoor one if possible as it's more reliable.
Aerial cable cut
- Thread starter Vicario
- Start date
Personally, I would use F type connectors and female coupler.
You only need two male f-type connectors so the screw on types will be the cheapest option. Amalgamating tape will help keep the connections dry.
You only need two male f-type connectors so the screw on types will be the cheapest option. Amalgamating tape will help keep the connections dry.
^ This.
this kit contains all the bits necessary
www.aerialsandtv.com
Cable joint kit – A.T.V. Poles, Brackets, Clamps & Aerials
www.aerialsandtv.com
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Having repaired hundreds of cut aerial downleads over 25+ years in the trade, joining it on the outside wall is completely fine and won't noticeably degrade your Freeview signal—provided you watch out for one major trap that ruins 9 out of 10 DIY repairs:
1. The 'Drinking Straw' Water Trap (Check Cable Type First):
Before joining, inspect the cut ends closely:
- If the cable is older brown coax with air-spaced polyethylene dielectric (you'll see five or six tiny hollow air chambers inside around the copper core), it behaves like a drinking straw in the rain. Capillary action draws rainwater a metre or more up inside the cable. If you join wet coax, moisture attenuates high UHF Freeview frequencies (BBC/ITV HD multiplexes) and slowly corrodes the copper braid black.
- Cut back each end by 30–50mm until the copper braid is bright, shiny, and the white/clear insulation is bone dry.
- If it is modern black CAI-benchmarked WF100 or CT100 (solid foam dielectric with copper foil and copper braid), water cannot easily travel along the core, which makes the repair much easier.
2. Correct F-Connector Termination:
- Strip back about 15mm of outer black/brown PVC sheath cleanly without nicking the copper braid.
- Fold the braided copper wires neatly back over the outer sheath. Make 100% sure that not a single stray copper hair touches the centre solid conductor—even one microscopic hair touching will short out the RF signal completely.
- Leave 2mm of the inner dielectric showing, strip the rest to expose the solid copper centre core.
- Screw the F-plug firmly on until the dielectric sits flush against the inner hole of the nut, and the centre solid copper 'stinger' protrudes exactly 2mm past the rim of the F-nut.
- Couple the two male F-plugs together with a threaded female-to-female F-barrel coupler.
3. How to Apply Self-Amalgamating Tape (Don't Wrap It Like PVC Tape):
- Peel the backing film off the self-amalgamating rubber tape.
- Stretch the tape by about 50% of its relaxed width as you wrap it—stretching is what activates the chemical vulcanisation that causes the layers to fuse into a solid waterproof rubber sleeve.
- Start wrapping 50mm below the joint, overlap each turn by 50%, work your way upwards past the join, and finish 50mm above it. Wrapping upwards creates a shingle effect so rainwater naturally runs off the overlaps rather than catching under the edges.
- Finish with 2 tight layers of standard black PVC insulating tape over the top. Self-amalgamating rubber will perish under direct solar UV over 2–3 summers if left unprotected; the outer PVC layer shields it from UV breakdown.
4. Mechanical Support & Drip Loop:
Don't let the joint dangle unsupported in the wind, or flexing will work the copper core loose over winter. Fasten a round 7mm cable clip to the masonry directly above and below the joint, and form a gentle downwards 'drip loop' below the join so any water running down the wall drips off the bottom of the loop rather than sitting against the repair.
1. The 'Drinking Straw' Water Trap (Check Cable Type First):
Before joining, inspect the cut ends closely:
- If the cable is older brown coax with air-spaced polyethylene dielectric (you'll see five or six tiny hollow air chambers inside around the copper core), it behaves like a drinking straw in the rain. Capillary action draws rainwater a metre or more up inside the cable. If you join wet coax, moisture attenuates high UHF Freeview frequencies (BBC/ITV HD multiplexes) and slowly corrodes the copper braid black.
- Cut back each end by 30–50mm until the copper braid is bright, shiny, and the white/clear insulation is bone dry.
- If it is modern black CAI-benchmarked WF100 or CT100 (solid foam dielectric with copper foil and copper braid), water cannot easily travel along the core, which makes the repair much easier.
2. Correct F-Connector Termination:
- Strip back about 15mm of outer black/brown PVC sheath cleanly without nicking the copper braid.
- Fold the braided copper wires neatly back over the outer sheath. Make 100% sure that not a single stray copper hair touches the centre solid conductor—even one microscopic hair touching will short out the RF signal completely.
- Leave 2mm of the inner dielectric showing, strip the rest to expose the solid copper centre core.
- Screw the F-plug firmly on until the dielectric sits flush against the inner hole of the nut, and the centre solid copper 'stinger' protrudes exactly 2mm past the rim of the F-nut.
- Couple the two male F-plugs together with a threaded female-to-female F-barrel coupler.
3. How to Apply Self-Amalgamating Tape (Don't Wrap It Like PVC Tape):
- Peel the backing film off the self-amalgamating rubber tape.
- Stretch the tape by about 50% of its relaxed width as you wrap it—stretching is what activates the chemical vulcanisation that causes the layers to fuse into a solid waterproof rubber sleeve.
- Start wrapping 50mm below the joint, overlap each turn by 50%, work your way upwards past the join, and finish 50mm above it. Wrapping upwards creates a shingle effect so rainwater naturally runs off the overlaps rather than catching under the edges.
- Finish with 2 tight layers of standard black PVC insulating tape over the top. Self-amalgamating rubber will perish under direct solar UV over 2–3 summers if left unprotected; the outer PVC layer shields it from UV breakdown.
4. Mechanical Support & Drip Loop:
Don't let the joint dangle unsupported in the wind, or flexing will work the copper core loose over winter. Fasten a round 7mm cable clip to the masonry directly above and below the joint, and form a gentle downwards 'drip loop' below the join so any water running down the wall drips off the bottom of the loop rather than sitting against the repair.
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