NE Atlanta suburb - attic installation

origin8502 · 9-Dec-2010, 8:34 PM

Total neophyte when it comes to ditching Comcast, but dagnabit I'm determined now. I've been reading for a few days, but I don't have a clear-cut definitive answer for a preferable in-attic antenna installation to feed 3 TVs on two different floors.

TVFool report: http://www.tvfool.com/?option=com_wr...81a3c23ea5d80a

I'm mostly interested in the stations listed in Green, but wouldn't balk at getting the Yellow as well. I couldn't even tell you what the stations are in Red (excepting ION and PBS) so I figure I wouldn't miss them.

As you can see I have a straight shot LOS for a majority of the wanted stations with azimuth roughly between 210-220 degrees so I'm hoping this is going to be a rather simple review.

I am inclined, if feasible, to place the antenna in my attic which sits roughly 30 feet above street level though my home resides halfway down a declined street. Our roof is wood with asphalt shingles and LOS points a bit towards brick siding on our home though antenna mount should be above the brick line. There is some aluminum ducting in the attic, but the insulation is not aluminum backed.

Could anyone provide some antenna suggestions? Signal is pretty good for my location, but I don't know if the attic placement and distance to TVs would require a pre-amplifier.

Dave Loudin · 9-Dec-2010, 8:55 PM

You need only a modestly directive antenna, but that antenna needs to be able to receive high-VHF (for NBC, ch. 10 and a PBS station on ch. 8) along with UHF channels. A Winegard 7694P or an AntennaCraft HBU-22 will fit the bill. You may have to experiment with the direction to point the antenna for best results (somewhere between due south and 245 degrees.) Do NOT use a preamp, as the multiplicity of strong signals will overload it. You should have enough signal to drive two TVs.

Quick math: the goal is to have a noise margin of 10 or more to protect against random stuff. Attic installs can knock a good 20 dB off of signals, but you will have 8 dB of antenna gain, so subtract 12 from all the noise margins of the stations you'll be pointing at and you'll see that you still have plenty left over for cable losses.

John Candle · 10-Dec-2010, 1:34 AM

All channels are very strong. Get one of these antennas and try it at the different tv locations , I think that indoor antenna will work fine. http://forum.tvfool.com/showthread.php?t=233 , http://www.kyes.com/antenna/pointing/pointing.html

Dave Loudin · 10-Dec-2010, 3:11 PM

John, he's feeding 3 TVs, so a fixed antenna in the attic is the preferrable way to go.

John Candle · 10-Dec-2010, 3:20 PM

An indoor antenna at each Tv location is A Ok.

Dave Loudin · 10-Dec-2010, 5:18 PM

Check the path profiles. If he puts a TV in the basement, I don't think he'll get the same results. Attic or outside installation sans preamp is guarenteed to work.

origin8502 · 10-Dec-2010, 5:40 PM

Hey guys,

Thank you very much for your thoughts. Currently the coax cable (internet) feed is routed into the unfinished basement and this is where our splitter for every currently wired room is located. I'm tempted to go with the individual antennas just because the setup would be soooo convenient, but I think I do prefer the idea of having a single mount upstairs, out of site. However, I'll have to find a way to run the cabling from the attic down past the 2nd and first floors and into the basement. Could the length of that run potentially be problematic?

As an aside, the unfinished basement is a walk out daylight one with the walk out side conveniently facing pretty much exactly where the antenna(s) should point. Three sides of the basement are cinder block interior with brick exterior, but that back side is wood framing, windows, and unbacked insulation.

I suppose I could put that larger single antenna in the basement first just to see how reception would be before affixing permanently in the attic.

John Candle · 11-Dec-2010, 7:18 AM

If you have a tv in the basement to connect , then I suggest putting the antenna on the roof or attic. Tv reception with a indoor antenna will not be good in a basement. As an experiment you can get NON AMPLIFIED indoor antenna and try it at the Tv locations including the basement. If put a Tv antenna in the attic or on the roof , DO NOT use a amplifier. The Tv transmissions are very strong at your location. To get the coax from the basement up to the attic or roof , a sewer vent pipe will go from the basement up to top of the roof , run the coax along the outside of the sewer vent pipe.