Cabling

There are few things people make a bigger mess of than cabling, especially builders. When I was installing satellite TV I spent a large portion of my time correcting other people's cabling mistakes. It is the most common cause of failure in satellite TV systems. It saves everyone a lot of time and money if it's done right the first time, here's how.

Don'ts

• Never use anything other than a coaxial cable stripper to strip coaxial cable, they're cheap easy to use and always strip the right amount of insulation without damaging the cable. I've seen people use wire cutters, scissors, wire strippers, even box cutters. Please do not do this, in the best case scenario you will have poor performace, in the worst case scenario you may actually damage equipment by shorting the shield to the center conductor.

• Do not staple coaxial cable, ever. Only use actual cable clamps. Staples penetrating the insulation are the second most common cause of shorts, and the pressure from the staple gun deforms the cable's dielectric, decreasing performance.

• Never fasten cables inside walls, or in any other hard to access place. There's a good chance the cable will need to be upgraded or replaced at some point, and it's much easier when you can just tie the new to the old and use it to pull the new cable.

• Do not buy RG-59 cable. This only works for over-the-air and cable TV, and it's not even very good at that. Use good quality RG6.

Choosing Cable

In general you'll want to buy the highest quality cable, within reason. If it has any common electronics manufacturer's name on it (Philips, Magnavox, etc) then it's probably crap. The standard grade of cable these days is RG-6, with a 60% aluminum braid and 100% aluminum foil shield, and will be rated to carry signals up to 3000 MHz. The center conductor may be made of copper plated steel or solid copper, depending on the application. The older RG-59 type of cable should never be used for new installations, since it's unable to carry signals above 900 MHz, making it useless for today's high bandwidth networks.

The higher the frequency, the greater the losses in any given cable will be. For extremely long runs, such as over 100 meters for 1450 MHz or over 40 meters for 2150 MHz you may have to invest in RG-11 grade cabling. For any application where the cable is responsible for carrying voltage to remote equipment (LNBs, switches, preamps) the total cabling run shouldn't exceed 40 meters when using a cable with a steel center conductor. High current equipment like the block-upconverters on satellite internet antennas should only be installed with solid copper cable.

 The top brands that you'll want to look for are Commscope "Bright Wire", Belden, PCT/Channel Master, and Eagle Aspen, in that order. Please do not waste money buying gimmicky cables with weird dielectrics and extra braids and stuff, none of that really helps and sometimes, as is the case with "quad shielded" cabling, actually decreases a cable's performance.

Stripping the Cable

When stripping a cable it is essential to expose the right amount of each layer, and to do so without damaging the cable. There is a very specific tool meant to do exactly this and I strongly suggest you use it. The best device I've found is the Paladin Tools Data Shark, which costs less than $10 and has a notched blade to avoid cutting into the center conductor. All connectors are designed to be inserted onto a cable which has had ½" of the outer jacket and  ¼" of the dielectric stripped. It's important to cut the dielectric evenly, and without crushing it. Fold the braid wires back and make sure none of them are touching the center conductor.

The cable on the left was stripped with a Data Shark, the one on the left looks to have been stripped with a wirecutter.

Connectors

There are a wide variety of connectors available, but there are only two which are currently in wide use on a professional level - compression and hex crimp. Both require a specific tool to be used properly, which costs around $20-$50. Hex crimp connectors are inexpensive and durable, but are not meant to be used outdoors. My very favorite brand of hex crimp connectors are Steren, due to their tarnish resistance and ease of use. Compression connectors are more elaborate, featuring an annular sleeve that locks the cable in place and forms a weathertight seal. Compression connectors are supposed to offer less signal resistance than hex crimps at high frequencies, but I've been unable to measure any significant difference in signal quality at up to 2150 MHz.

This is very bad practice. The dielectric is chewed up, the center conductor is not long enough on the top one, and too long on the bottom one. The braids should never stick out past the connector, and although it's not visible in this picture, the bottom connection is shorted because a braid is wrapped around the center conductor.

This image shows proper connector installation. The dielectric is flush with the inside of the connector, the connector is compressed fully and evenly around the cable, and there are no braids visible. The center conductor should protrude out of the connector by about the thickness of a nickel.

Waterproofing

All outdoor connections should be compression type connectors, and should be torqued to 22 in-lb with a torque wrench. Don't exceed 22 in-lb, since you can destroy equipment by overtightening. The actually make a tool specifically for this. Try to find compression connectors that don't have exposed plastic parts. For example, I've seen Thomas & Betts, PPC, and Digicon connectors fail when their plastic sleeves cracked due to sun damage. The best ones I've found are the PCT one piece nickel plated brass compression connectors, which have an all-metal construction and even includes a little washer to help seal up the inside of the connector. For extra insurance, you can fill outdoor connectors with silicone grease.

Outdoor connections should never be made with the cable angled downward toward the connector. Water tends to drip down the cable, and can enter the cable much more easily that way. When possible, make connections with the cable hanging below the connector. Devices like switches and grounding blocks with connectors on opposite sides are meant to be installed horizontally, and with the cable angled downward and away. Down-coming cables should have 4" drip loops before entering a structure or being terminated with a connector.

For the most part, rubber boots, washers, etc are unnecessary when the connectors are properly installed and torqued. I do, however recommend capping any exposed ports on outdoor switches, splitters, and LNBs.