Installing Radio and TV antennasby Lorenz Prem
Indoor antenna often work well enough to receive FM signals. AM signals and other types often require line of sight. To receive these signals at reasonable level an out door antenna is needed. Lets take a look at what's needed to install one.
1) An antenna mast
Most antennas are designed to be installed on an antenna mast. Mast range in size from a pole a few feet long to a telecommunications mast measuring 10-30ft. Most homeowners will get by with a simple pole mast.
The ChannelMaster Super Mast was used in this project.
2) A location to mount the antenna mast
An antenna works best in the open air. Ideally it is placed at the highest point in the area. Often this is not possible. The generally accepted guidelines are 3-5ft above the highest point of your home, and as far away from other structures or trees. If you are planning to receive a signal that requires line of sight, make sure you can see the transmitting antenna from where you are mounting the antenna.
3) Mast mount
Once you picked a location, you need to find a way to mount your mast to the house. There are a number of ways to accomplish this.
- Wall mount: Wall mounts attach to vertical surfaces like the walls of your home. Unless your home sits on a hill, which allows the antenna to be installed on the side of your home, make sure the wall-mount allows the antenna mast to clear the roof overhang. (on Amazon)
- Gable Mount: A gable mount is a simple metal bracket that attaches, as the name implies, to the gable of your home. It is simple to install and very sturdy. It's drawbacks are that the antenna can probably be seen from the ground, and that that there are probably only two gables, or two locations for the antenna, on your roof. (on Amazon)
- Through the roof mount: This mount can be installed anywhere on your roof giving you the best antenna placement options. Installation requires holes to be drilled through the roof into the sheeting. Professional roofers will tell you that this cannot be done in a perfect manner. The joint will eventually leak, if left alone. If you use a through the roof mount, plan on re-caulking the connection points at least every two years.
Antennas come in many shapes and sizes. Selecting an antenna goes beyond the scope of this article. In general larger antennas produce a higher quality signal. There is no substitute for physical bulk no matter how ugly this makes the antenna. Different frequency bands require different antennas. There is no one-size-fits-all solution here. Figure out which signals you want to receive, and buy an appropriate antenna.
5) Antenna cable and connectors
RG6 coax cable (on Amazon) has become the standard cable used for antenna and cable TV installations. It is shielded and higher quality than RG59 cable. Given the relatively low cost of this cable, there is no reason to save money in this area. If your install requires less than 100' of cable, purchase RG6 coax cable. Installations with longer cable runs either require a signal amplifier, or high gauge cable.
There a several different coax connectors on the market. Compression fittings are the highest quality option for outdoor installations. Once installed, they produce a quality signal and a water tight seal. Spend the extra money an purchase the tool required to install these fittings. If your antenna does not produce the signal you are hoping for you can immediately eliminate the connectors as the source of the problem. Professional installers have learned not to save pennies in this area.
6) Antenna Matching Transformer:
This low-cost part transform the signals produced by the antenna into a signal compatible with the 75-ohm wiring system. In most cases your antenna package will not include this part, because the matching transformer must match the rest of the system. Check what transformers the signals you want to receive require. For radio signals(FM, AM, ...) a simple 300-75ohm matching transformer will work perfectly. (on Amazon)
7) Ground wire and grounding block
By code every antenna installed in the US must be grounded. This is one of the sections in the code you should pay attention to. Ungrounded antennas are lightning magnets. The same principles that make an antenna location work, also make the antenna increase the lightning strike risk of your home. A proper grounding system mostly mitigates this risk.
The code calls for a 10 gauge ground wire to be run from a grounding block (on Amazon) to the closest grounding point available. That can be the house's ground rod, a water fixture, or the electrical system. Check the code for detailed requirements.
The coax cable must also be grounded. Without proper grounding signal strength will be degraded. You really want to pay attention to this requirement as well. Install a coax grounding block near to the point the cable enters the structure. Connect the block to a suitable grounding point.
8) Electrical box and TV wall plate
The other end of the antenna cable terminates in an electrical wall box in your home. Routing the cable through the exterior wall can be a challenge. Often it is simpler to feed the cable into a crawl space or attic and enter the living space from below or above.
The wall plate used for antennas is typically a standard F-type plate used for cable TV. If you have come this far, installing the wall plate will be a snap.
- Antenna mast
- Antenna mount
- RG6 cable (or better)
- RG6 connectors
- Grounding block
- Matching Transformer
- RG6 wall plate
A quality antenna will add a quality TV and/or radio experience to your home. The building code's requirement for the antenna system to be grounded is essential for safe operation. Do not cut corners, and mind the power lines when you install your gear.