This is a work in progress. It is posted due to all the questions concerning this matter. What is missing is properly grounding the antenna.
Another great site is HDTVPrimer. Erecting a TV Antenna
_____________________________________________________
So you want to install an antenna,
Having worked in this field years ago and still getting questions now and then, please use these steps to avoid common pitfalls and mistakes. The CAPS represent many of the wacky things I've seen in my career. Antennas are fairly simple devices which can sometimes cause a lot of headaches to get right. Following these basics should get you in the neighborhood with the least amount of effort. I recommend starting with an inexpensive UHF/VHF indoor antenna first. You might be surprised and it will also give you a starting reference point. A step up for HDTV is the Silver Sensor from www.gemini-usa.com for $34.99. If you are within 15-20 miles of the tower you must START HERE - DO NOT go and buy the biggest outdoor antenna!
OUTSIDE ANTENNA
An antenna is excited by radio waves which produces a certain level of signal. They come in all kinds of sizes and shapes. The most common are VHF/FM/UHF combos and UHF only. HDTV reception can be either UHF or VHF. How much signal you will need depends on your distance, elevation and buildings within 4 blocks. The key is to get the signal level just right. Too little or too much can cause problems. Go to http://www.antennaweb.org/aw/welcome.asp
Click on "choose an antenna".
Inserting your address is recommended or use zip code and answer the two remaining questions. Click submit.
You now have a listing of all stations you have a chance of receiving and print it. At the top of the listing click on "map station distribution" and print it also. The stations on the bottom are the furthest away and you may not even recognize them. From the bottom work your way up to your local analog stations and click on one of them in the same color group. Do not misunderstand this step and click on the DTV channels. You will need to use your NTSC stations as your antenna selector guide for now since they are not transmitting DTV at full power yet.
Now you have information that tells you what antenna you need, if a preamp is required, where the transmitters are and the "real" DTV channel numbers. The antenna is cheap. Major expenses will be all the other stuff and your labor. If all the transmitters are basically from one direction you probably will not need a rotor. If not make a rotor part of the budget because most installations need it to avoid problems or to get that tough to receive channel. Use RG6 cable and the proper connectors. It is assumed you know how to properly terminate the cable.
INSTALLATION
The FCC has legally allowed you to mount an outside RF antenna of any size up to 12 feet above the roof line regardless of your home owners association rules and regulations. See the post following this one for more information.
Buying the antenna and associated stuff was the easy part. Installing it is work. In the installation make allowances for the possible rotor and wiring - you will appreciate this step later if you need one. Remember once you get the system installed changing the antenna itself is easy and cheap so don't sweat what kind of antenna you bought too much. Installing it outside is always preferable over the attic. If you have a multi level dwelling and live in a subdivision that does not allow roof top antennas you may be able to mount it under a rear deck which is still better than the attic ( worked great for me - might not for you )or in the backyard. Place the antenna for the least obstruction of anything between it and the direction it will face ( if possible ) and point it towards that direction using the "map" you printed out. Pay attention to boots, covers and seals which keep out the elements. Preamps come in 2 sections and I recommend it have variable gain rather than fixed. One part is the actual preamp and it belongs on the antenna mast as close to the antenna as reasonably possible, NOT in the house. Allow SLACK for turning the antenna by hand or with a rotor. The other part is the power supply and that is what goes in the house. Make sure it is accessible and within VIEW of the TV so you can tweak the gain. It must have live AC at all times so DO NOT use a switched outlet. Terminate the cable PROPERLY with the CORRECT connectors with the proper CRIMPING tools or you will detune the system. NO, you can't just use pliers and "squish" it or "pinch" it on.
Unless you're in the biz you will be using the TV tuner as your signal strength meter. Turn the gain on the preamp all the way down and hook up your cable to the TV and find the strongest UHF station. This means, the least amount of RF noise - not ghosts. If it is clear (RF noise) you may be done. If you are not sure what the front part of the antenna is then turn it 180 degrees and check your results. One direction will be better than the other. Once you have confirmed this then go to the preamp power supply and turn up the gain. You will find a point where the picture becomes the clearest - this is where you should leave it - DO NOT turn it up higher. Remember, not too much or too little signal is the goal - you want it just right. At this time you might want to experiment with tweaking the direction for best overall response. If you have a rotor use it. Now move the cable to the HDTV receiver input for OTA ( over the air ). DO NOT use the satellite input jack. Auto programm the channels first. What channels were skipped should now be entered manually using the list of stations you can receive which you printed earlier. The "real" DTV channel numbers are on this list. Using the "map station distribution" print out you may find your answer as to why you are not picking up certain stations - the antenna is not pointing that way and you may need a rotor. For most installations you are now done and ready to go "WOW", what a picture.
This is not a perfect science.
TIPS, SUGGESTIONS, FYI
You may be the one of the lucky folks who get everything with little fuss and no rotor. DTV is a digital format. You will get one of three results, a beautiful picture, a beautiful picture that comes and goes, pauses, blocking, intermittent sound(intermittent reception), or no picture at all.
Intermittent DTV reception is caused by various things and is typically due to ghosting and sometimes low signal level. Having a rotor or installing one could easily eliminate many of these problems. Changing the base location or height by 5 feet may help.
No DTV pictures is typically due to very heavy ghosting or the signal level being too low and on rare occasions too high. Since broadcasters are not running at full power a preamp may be beneficial.
If your receiver has a signal strength meter use it. It will show a signal even though a picture is not displayed. This can be very helpful for tuning in a known station. Bear in mind that this type of meter is actually measuring bit error besides signal strength. If you know that you should be receiving a certain station and the meter is intermittently showing a signal you are probably dealing with heavy ghosting. Relocating the antenna may help.
If you have a rotor use it and sweep the full 360 degrees. In some cases having the antenna pointed wrong may work.
Play with the preamp gain. Preamps can also cause problems since they increase all the noise and ghosting along with the signal level. You might have to increase or decrease the gain for DTV reception from the setting you made earlier. Technically it is best to not use a preamp and simply run the cable directly without any splices - do not get hung up on this issue though.
If you used an indoor antenna for a reference than you should get better reception with the outside antenna using the analog TV tuner. If not suspect something defective. Bypass the preamp completely first. This should be better than the indoor antenna. If not change out the balun on the antenna. If you still get nothing inspect the antenna and make sure everything is connected properly - it may defective.
Everybody hates this but it's true. Moving the whole installation just five feet somewhere else or further away or at the other end of the house may resolve problems. What stinks is that the only way to find out is to do it.
Above all there are times when what works in a certain install defeats all logic so be open to alternatives.
The antenna is a broadband device with it's own unigue characteristics across the complete band. Changing to a different brand of antenna might help with tough to receive stations. They all have different peak frequency signal points due to design. There is a technical method to figure this out but finding the specifications is nearly impossible. You will just have to experiment.
When installing indoors, an attic, you may need to go one size larger to overcome the signal loss. On the other hand you may see little difference with a different antenna because the attic is causing more reflections than outdoors.
Being in valleys, the sides of valleys or on hills causes the most problems. You may need to compensate with antenna size, preamp gain or location in terms of where and how high. You could get a huge reflection or huge loss on one channel in these situations which falls outside the normal gain required for everything else making that channel useless.
Some will say following all these steps is unnecessary. Granted. If you should have problems then follow the steps completely. I laid it out this way so what is happening will make sense so you can trouble shoot correctly to find your problem.
FINALLY
It ain't always easy. That's why satellite and Cable have 70% of the delivery market and why cable needs to get on the ball for delivering DTV signals. In Atlanta there is a retailer who provides "turn-key" antenna installs. It is fully guaranteed or your money back. They supply a remote controlled rotor and what ever else for that particular install. It runs $400-$700.00. Given the above it is easy to appreciate why they charge that much.
Good luck,
Richard Fisher