Let’s say you and your wife were doing some gardening. In the process, someone, maybe your wife, cut the underground cable with her shovel, after she specifically warned you not to do that.  It’s not important to place blame here, what’s important is to fix the cut.  You need to make a splice connection. But you need a waterproof splice so that it can withstand moisture once you bury it again.


Waterproof coaxial splicing kit
Credit: gibbon

The quickest, cheapest way to repair it is with a waterproof coaxial splicing kit.  Radio Shack sells these in their stores, and through Amazon for about $5.  The kit consists of a metal crimp connector to rejoin the signal carrying parts of the cable, rubber boots to cover the connection, and sheets of rubber mastic material to seal up the entire splice. If you’ve ever crimped a connector onto indoor coaxial cable, you have all the skills you need, so let’s get started.

1. Clean Up the Cut

Once you’ve dug out around the cut, you can assess the damage.  Clear out a few inches below the cable to give yourself room to work. If you (or someone you’re married to, it’s not important which one) made one clean cut, you can simply splice it back together.  If the cut mangled up a lot of cable, or you made 2 cuts, you will need to make 2 splices with a new piece of cable between them.  The kit contains enough parts to make 2 splices (but it does not include extra coax cable).

2. Strip the Ends

Put the boots on over the cable first and then strip the cable back just like you are going to put on a crimp-on connector.  There are instructions on the package that specify how far back to strip each layer

Coax cable ends stripped
Credit: gibbon

3. Make the Connection

Push the copper cable ends in to the screw connector, and tighten the retaining screws.  Then crimp the ends of the connector.  The crimping tool is also available at Radio Shack.

4. Cover the Connection

Push the two rubber boots together over the splice until they seat.  At this point you can test the connection by checking your cable signal.  If your signal looks good, you can finish up.  If it doesn’t, you may need to call the pros.

Splice boots and mastic
Credit: gibbon

5. Seal the Splice

Peel the backing off two of the sheets of the rubber mastic, and place the sticky sides together around the splice to form a waterproof sandwich.  Starting at the splice and working outward, press all the mastic together firmly, especially along all the edges.  You want to trap as little air as possible, and make sure you have a good seal all the way around.

Sealed splice
Credit: gibbon

Congratulations! Now just re-bury the cable and you're done.