TV Fool

TV Fool (http://forum.tvfool.com/index.php)
-   Help With Reception (http://forum.tvfool.com/forumdisplay.php?f=7)
-   -   Attic Antenna with trees (http://forum.tvfool.com/showthread.php?t=14444)

OTAonRockyTop 24-Apr-2014 3:03 PM

Attic Antenna with trees
 
So I recently cut the cord after doing the math on what I'm paying to watch the occasional sports game and some old re-runs. It doesn't make sense. I don't like making threads and asking to be spoon fed info, but I've read plenty of threads and it seems that I would be better off asking for application specific advice.

After my Roku box, the only thing I need TV for is live sports. So I'm really only interested in the networks, i.e. WATE, WVLT, WTNZ and WBIR. Here is my tvfool report:

http://www.tvfool.com/?option=com_wr...e1c6873a1bf21a

Seeing that I'm 5 miles from the broadcast signals, I figured this would be a simple deal, so I got a Mohu Leaf for the living room and an Amazon knockoff of the Leaf for the bedroom. Well, it turns out that I can't get a decent signal with these. Both signals cut out about once every 10 seconds like clockwork.

Being ignorant at the time, I thought amplification would fix my problems, so I bought a preamp from Walmart. Just a little RCA deal, not sure of the model number, but I'm hoping to be able to return it as it did nothing to help the problem.

I have a direct LOS to the ridge with all the towers on it, but I think my main concern is that my back yard is a tropical rainforest. And there's no way possible to mount an antenna anywhere on my property to avoid the signal passing through the tree line, short of a 100+ foot tall antenna.

My girlfriend is convinced that we don't even need TV, even though she's a huge college football fan, and I've tried to tell her that we won't see any games next season without network channels. Anyway, I've promised her I would do everything within my power to avoid an "ugly" outdoor antenna. It is an option, but I would like to try an attic install first.

I see that I have one channel I want that is VHF High, with the rest being UHF, and that is WBIR (NBC). Thankfully, everything I want to pick up is broadcast from about 320 degrees to mag N.

Sorry for the long lead-in, but can anyone suggest a good antenna that may work for me in the attic, and is a larger antenna going to help me with my tree line problem? I plan to split the signal to both TV's in the house, and eventually may add a third in the spare bedroom. The coaxial runs will be approximately 40 feet to the longest TV if attic mounted. Add another 20 feet or so for a roof mounted installation. What other equipment might I need? Any advice is appreciated.

OTAonRockyTop 24-Apr-2014 3:06 PM

I should add that the nearest trees in the direction signals are coming from are probably 100 feet or more from the house, if this affects anything. The slope of the terrain is very steep downgrade leading away from the house. We're up on a hill, so not the entire woods is blocking the signal, just the first 50 feet or so worth of trees.

ADTech 24-Apr-2014 3:18 PM

Getting your antenna up in the air as high as possible and mounted as far back away from that tree line are your best options short of mounting the antenna in a tree or cutting or bulldozing the woods.

OTAonRockyTop 24-Apr-2014 3:25 PM

Well there's no way to mount above the tree line, as most of the trees are very mature >100' tall monsters. Many of the trees in the neighbor's yard are covered in kudzu and I'm afraid that when it turns green and gets leaves back, it will just amplify the problem.

The only way to get any further from the tree line is to mount in the front yard, which is NOT happening under any circumstances.

So, any other advice? The best I can do is mount on the roof, but I would like to get an antenna that I can try in the attic first and move if that doesn't alleviate my issues. I'll add that WBIR (VHF) does come in considerably better on the Mohu than the other channels, but it still has reception problems on occasions.

The woods are not on my property, and cutting anything down is not feasible. My fallback is to upgrade my Internet package to include local channels and HBO, but I would love to avoid this and just go OTA digital signal.

tomfoolery 24-Apr-2014 5:20 PM

Well, if it makes you feel any better, my FIL has an HBU-22 aimed right into a 25 ft high wall of coniferous hedge that you can't see anything, even daylight, through with a fool report very similar to yours, but his is mounted outside. He gets flawless reception.

Doesn't mean it'll work for you, of course, especially in the attic, but if it were me, I'd get something like the HBU-55 (high gain, tight pattern, UHF plus H-VHF) and try it. Since all your towers are in a tight pattern, you might get lucky, though you might have to mount it outside in the end.

Or not. It's easy to spend my hypothetical money, since it doesn't actually cost me any real money. ;)

OTAonRockyTop 24-Apr-2014 8:21 PM

Quote:

Originally Posted by tomfoolery (Post 43587)
Well, if it makes you feel any better, my FIL has an HBU-22 aimed right into a 25 ft high wall of coniferous hedge that you can't see anything, even daylight, through with a fool report very similar to yours, but his is mounted outside. He gets flawless reception.

Doesn't mean it'll work for you, of course, especially in the attic, but if it were me, I'd get something like the HBU-55 (high gain, tight pattern, UHF plus H-VHF) and try it. Since all your towers are in a tight pattern, you might get lucky, though you might have to mount it outside in the end.

Or not. It's easy to spend my hypothetical money, since it doesn't actually cost me any real money. ;)

Thanks for the reply. I'm worried that it's not just a single wall of trees, but a dense forest with multiple layers of trees needing to be passed through. HBU-55 seems like it might be overkill? Would an HBU-22 work? I'm not sure the 55 would fit in my attic.

GroundUrMast 24-Apr-2014 9:18 PM

Even the large HBU-55 may not be enough to provide 100% reliable reception in the conditions you're describing. But, it gives you a far better chance. The attic may not be an awful location for reception, but you are giving up some precious signal quality... The only question is how much.

tomfoolery 24-Apr-2014 11:48 PM

You could use a smaller version, with wider beam width and lower gain, but trying to receive already weak and/or multipath signals from inside an attic that will further weaken and reflect/refract them is going to be tough I would think. But here's the web page, with links to the specs. These aren't the only ones out there either, of course.

http://www.antennacraft.net/Antennas/AntennasHBU.html

Tower Guy 25-Apr-2014 12:32 AM

I'd be looking at the insulation in the attic to make sure there is no foil. It could be inside and visible or between the sheathing/roof deck and the siding or shingles.

You may simply try moving the antenna in the attic to find a "hot spot".

An amplifier is likely to make things worse. A small directional antenna (ANT-751 or HBU-11) is a better choice than the leaf clone.

OTAonRockyTop 25-Apr-2014 12:01 PM

Quote:

Originally Posted by GroundUrMast (Post 43599)
Even the large HBU-55 may not be enough to provide 100% reliable reception in the conditions you're describing. But, it gives you a far better chance. The attic may not be an awful location for reception, but you are giving up some precious signal quality... The only question is how much.

So the trees really are that big an issue, huh? I was hoping being 5 miles away from the towers would make this a piece of cake. :mad:

I am probably just going to mount it on the roof. I don't want to go too high, because I'd like to stay under the leaf canopy of the thickest trees I think. But I don't think I could reach the thickest part if I tried.

Quote:

Originally Posted by tomfoolery (Post 43603)
You could use a smaller version, with wider beam width and lower gain, but trying to receive already weak and/or multipath signals from inside an attic that will further weaken and reflect/refract them is going to be tough I would think. But here's the web page, with links to the specs. These aren't the only ones out there either, of course.

http://www.antennacraft.net/Antennas/AntennasHBU.html

Can you explain multipath? Is that due to the trees blocking partial signal?

Quote:

Originally Posted by Tower Guy (Post 43604)
I'd be looking at the insulation in the attic to make sure there is no foil. It could be inside and visible or between the sheathing/roof deck and the siding or shingles.

You may simply try moving the antenna in the attic to find a "hot spot".

An amplifier is likely to make things worse. A small directional antenna (ANT-751 or HBU-11) is a better choice than the leaf clone.

There is no visible insulation in the attic. I can directly see the plywood, and it's an asphalt shingle roof. I think I will try a directional antenna.

So I won't need an amp for ~50 to 60 ft of coaxial split to 2 TV's?

Thanks for the suggestions, guys! I think I will try an HBU-22 sometime in the next couple weeks.

ADTech 25-Apr-2014 2:56 PM

Quote:

So the trees really are that big an issue, huh? I was hoping being 5 miles away from the towers would make this a piece of cake.
I wish it were that easy. Sometimes it is, other times, it isn't It's a real-life example of Forrest Gump's mother's box of chocolates.

Several springs ago, I paid a visit to a visit to local viewer whose home was in the Affton area of St Louis county. If you look up Affton on the TVfool map, you'll see it's within a triangle formed by a number of the St Louis towers, most within 3 miles and visible to the naked eye if not for trees and surrounding homes. The trees were already in full leaf and it was a windy day. On my spectrum analyzer, I could see as much as a 30 dB reduction in signal power just by moving a dozen yards from where the tower was visible to where I was behind one of those mature silver maple trees. When the wind gusted, I could see notches as deep as an additional 20 db within the channel bandwidth. I've observed similar behavior at other tree-bound locations, so this wasn't a unique observation.

Now you can see why I'm so pessimistic that through-the trees reception is so apt to be unpredictable, especially with weak UHF signals.

Quote:

Can you explain multipath?
Multi-path occurs when:

1. There is some signal that, besides taking a straight line of sight path to the receiving antenna, also reflects or diffracts off other objects before arriving at the antenna at a slight time delay relative to the original signal.

2. The LOS path is blocked (hill, tree, building, etc) and the only signals that arrive are some chaotic mess of signals that are some combination of reflected and diffracted copies of the original, perhaps with some remnant of the original signal at some level of attenuation.

It's generally up to the tuner to try to sort out the mess and reassemble something that decodes well enough to be usable without excessive errors. When the error correction circuits get overwhelmed, there will be a visible defect in the video or an audio defect ranging from a minor blip in either up to a pixelated mess to a complete loss of any audio or video, depending on the severity of the signal impairment.

Ken Nist, on his website at http://www.hdtvprimer.com/ANTENNAS/fixes.html and http://www.hdtvprimer.com/ANTENNAS/siting.html sums it pretty well.

tomfoolery 25-Apr-2014 3:28 PM

Just to add, in the good old days, before DTV (which was most of my life), multi-path would make for ghost images on the screen. Weak, noisy signals were snowy. Where I grew up, it was both, as a ridge blocked the LOS to signals from NYC. But TV was watchable, albeit a bit ghosty and snowy. Worse when an airplane went overhead.

My parents' house now can't receive any signals from NYC, as they're too weak and too diffracted and too noisy for the digital tuner to handle. Basic cable is what they have, and it's the best reception they've ever had in the 53 years they've been in that house.

OTAonRockyTop 25-Apr-2014 3:33 PM

Quote:

Originally Posted by ADTech (Post 43628)
Multi-path occurs when:

1. There is some signal that, besides taking a straight line of sight path to the receiving antenna, also reflects or diffracts off other objects before arriving at the antenna at a slight time delay relative to the original signal.

2. The LOS path is blocked (hill, tree, building, etc) and the only signals that arrive are some chaotic mess of signals that are some combination of reflected and diffracted copies of the original, perhaps with some remnant of the original signal at some level of attenuation.

It's generally up to the tuner to try to sort out the mess and reassemble something that decodes well enough to be usable without excessive errors. When the error correction circuits get overwhelmed, there will be a visible defect in the video or an audio defect ranging from a minor blip in either up to a pixelated mess to a complete loss of any audio or video, depending on the severity of the signal impairment.

Ken Nist, on his website at http://www.hdtvprimer.com/ANTENNAS/fixes.html and http://www.hdtvprimer.com/ANTENNAS/siting.html sums it pretty well.

Thanks, that was helpful. I guess I'm going to try an HBU-22 unless anyone disagrees. I will remove the amplifier and try to return it, since I kept the packaging.

If that doesn't work, I guess it's back to spending $10 for basic cable channels. Better than the $100/mo I was paying before, I guess. That includes HBO though, so it's not a total waste.

tomfoolery 25-Apr-2014 3:58 PM

If you're set on the HBU-22, then if it were me, I would a) plan on mounting it outside for the cleanest signal possible to start, b) buy it from a place where I could exchange it for an HBU-44 or -55 (-44 is around 30" shorter than the -55) if it's just too weak or unclean, c) keep the amplifier for now, as you may receive a clean enough signal to amplify through the splitter (if needed), and d) not give up too easily if it's not satisfactory right away. The fact that you get signals that are fairly watchable with a leaf (or clone), inside the house, with wiring, metal, walls, etc. to mess the signal up in addition to the wall of foliage, is encouraging.

Good luck.

teleview 25-Apr-2014 11:35 PM

+=>

Above the Peak of the Peak of the Roof install a , www.antennacraft.net ,

HBU11K antenna aimed at about 312 deree magnetic compass direction.

Here is how to aim antennas , www.kyes.com/antenna/pointing/pointing.html.

Use a Real and Actual magnetic compass to aim antenna , do not trust a cell phone compass.

-------------

A antenna system amplifier will not be required.

GroundUrMast 26-Apr-2014 1:19 AM

IMO, if the horizon was free of trees and other obstructions the HBU-11 or HBU-22 would be appropriate.

Given the trees described, I have my doubts that these are ideal choices in this application.

teleview 26-Apr-2014 4:35 AM

+=>

For improved reception install a , www.antennacraft.net ,

HBU44 antenna in place of the , HBU11K .

----------------

Here are some above the roof antenna mounts.

www.ronard.com/909911.html
Use the , ronard(911) , 5 foot tripod antenna mount.

www.ronard.com/34424560.html
Use a , ronard(4560) , eave antenna mount.

www.ronard.com/ychim.html
Measure around the chimney and use a , ronard(2212) , ronard(2218) , ronard(2224) .

OTAonRockyTop 22-May-2014 4:02 PM

Just thought I would update this.

The HBU22 was pretty successful in the attic. I get no more dropouts except during really severe winds, which has only happened once since I've been sporadically watching in the past month.

I would love to get a 30 foot antenna and mount it outdoors, but this setup is GF/wife approved, and gets us 95% of the way there, so this is what we will stick with for the foreseeable future.

How can I tell if my setup needs amplification now? Signal appears strong, except my ABC broadcast appears grainy with some artifacts. It may just be their broadcast quality.

Right now, I'm only running the antenna to the living room TV, but it will be split and run to the bedroom TV in the future. I don't see a time that we will ever be watching both at the same time, if that affects signal strength. We rarely use the network channels.

I'm hoping that by the fall (football season), when we really have a need for the network channels, the leaves will have fallen for the most part and not even strong winds will interrupt our signal.

Also, I haven't really aimed and mounted the antenna yet. It's just sitting in the attic right now pointed approximately towards the towers. I'm hoping that a proper mounting and aiming of the antenna will help to alleviate the very rare signal dropouts as well.

My neighbors' setup with rabbit ears gave me good enough signal to watch March Madness without many dropouts when there were no leaves on the trees, so I have confidence that once they fall my signal will improve.

Tower Guy 22-May-2014 5:16 PM

Quote:

Originally Posted by OTAonRockyTop (Post 44143)
How can I tell if my setup needs amplification now?

Look at the strong signals on your TVfool report and assume that an amplifier is likely to make things worse.

GroundUrMast 22-May-2014 5:22 PM

TowerGuy is right, the signal levels shown on your report are strong. Here is a relatively simple test for basic antenna performance and determining if an amplifier is needed, http://forum.tvfool.com/showthread.php?t=13646. But in your case, simply focus on getting the antenna aimed well, and be willing to try outdoor mounting before adding the trouble an amplifier is likely to cause when facing such strong signals.

Loss occurs in the splitter and cabling. The loss is not expected to change when a tuner is turned on or off.


All times are GMT. The time now is 5:43 PM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright © TV Fool, LLC