Tale of a cable

[bernardgreen]

Thursday was a bad day for DIY

The picture on the TV in my neighbour's kitchen starting breaking up last week. The fault was obvious. The aerial cable ran across the flat roof then down the outside of the wall to a hole through into the kitchen. From the bedroom window one could see a damaged area of the cable. Obviously the problem was that damage. So on a hot sunny day I sit on the black felt roof and repair the joint. As luck had there was plenty of slack in a the cable so the damaged section could be cut out and a proper soldered repair was possible. Added to the sun's heat with the hot air gun.

TV picture not improved. After checking the whole length of the cable for damage, including a length under the insulation in the loft and finding no damage. Change ports on the distribution ampifier and still the picture is bad. I think "time to check the TV is not faulty" It was.

 

[DaveHerns]

Can you do a proper soldered repair to TV coax?

 

[bernardgreen]

Yes with care. It will create a very small impedance change but not enough to affect terrestial TV signals

First cut the cable at the point of damage removing the damaged section. Slide about a foot of heat shrink over one end. Remove enough of the outer sheath either side of the joint to allow the braids to be concertinered back away from the joint. It has to be far enough to allow heat shrink to be slid onto the insulation on both sides of the joint. Then the inner conductors are soldered together side by side. One of the pieces of heat shrink is then moved over the bare soldered conductor. This first piece is cut to fill the gap between the ends of the insulatiom and shrunk in place. The other piece is cut longer and covers the joint and a few milli-metres of the insulation. Then the braids are pulled to overlap each other and soldered together over the heat shrink. NOT over the insulation which may melt from the heat needed to solder the braids together. It is only necessary to solder a few of the strands of braid together. Then slide the foot of heat shrink over the repair and shrink.

 

[winston1]

Much better to fit 2 F connectors and a barrel, then cover with heat shrink or self amalgamating tape.

 

[DaveHerns]

That's what I would have done