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Thinkup
4-Jul-2010, 5:59 PM
New member here needing help if possible. I have a medium sized ranch style home and want to put up an antenna to pick up some over the air HD channels and need some advice on what antenna to get or some pointers on where to go for help. I'd like to put the antenna in the attic it possible but I can put it on the roof if it's a must. I'm mostly interested in the top 4 or 5 channels from my report but I'd like to look at my options. Attic vs roof, fixed vs rotating, the cost and how many channels I can get. Any help would be greatly appreciated. Some education or pointing me to some good reading would be cool because I'll be doing a friends house in the future as well. Thank you in advance.

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d9fbe18b1ae7fcf

Tigerbangs
5-Jul-2010, 7:18 PM
All of your major stations come from the Heiderberg Mountains West-Suuth-West of Albany. They are less than 22 miles away, but are obscured by hills at your location. Your situation really calls for a roof-top antenna, since the hills in your area block most of the signals, and if you have a metal roof, no signal of any kind will penetrate the attic. You don't need a rotator, since all the stations are in the same location, but you DO have 4 VHF stations in your market, including one low-band VHF station, WRGB, so you will need an all-channel VHF-UHF antenna aimed at 305 degrees, as measured by your compass. You shouldn't need a preamplifier unless you plan to run 2 or more TV sets from the antenna, or you have cable lengths longer than 100'.

I would recommend either a Winegard HD-7082P or a Channel Master Crossfire 3679 antenna. use the installation guide that I linked to you below, and you should get perfect TV reception when you are done.

http://www.winegard.com/kbase/upload/HD7082P.pdf
http://www.channelmaster.com/HD_television_antenna_Channel_Master_CM_3679_HDTV_Antenna_s/42.htm


and here is the link to the antenna installation guide:
http://manuals.solidsignal.com/AntInstallGuide.pdf

Thinkup
6-Jul-2010, 4:52 PM
Thanks for the quick reply. Awesome job. I'm a little sad to see that I can't get a smaller antenna to work on the roof or inside the attic. If I skip out on that one VHF low channel can I get something smaller. I'm not really all that interested in the UHF stuff either if it means I can get away with something smaller / with a better WAF or something.

Also, here is my friends report. He lives much closer to the towers and also wants to put something in the attic. Is he out of luck too? What are his options? Thanks in advance.

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d9fbe4ead3d4ece

Dave Loudin
6-Jul-2010, 7:30 PM
If I skip out on that one VHF low channel can I get something smaller.

Not if you want to watch CBS programs.

I'm not really all that interested in the UHF stuff either if it means I can get away with something smaller / with a better WAF or something.

I *think* you meant VHF. Skipping VHF reception means not seeing local CBS, Fox, MyNetwork, or NBC (probably) programs.

Sorry. Can't fight physics.

Thinkup
6-Jul-2010, 8:07 PM
So what I'm looking for is a directional VHF antenna that fill fit in my attic that will give me both low and hi VHF signals then? Is that correct? Is it even worth trying considering the hills around me? Is there a smaller unit that looks nicer that I can put on my roof? The stuff Tigerbangs recommended is super awesome for the geek in me but I'm only half of the decision making team at my house if you know what I mean. I'd rather a get sup-par antenna that will fit in the attic and only give me 4 channels then have my other half put her foot down on the big roof antenna and get nothing.

Any suggestions for my friends house by the way? He seems to be line of sight.

Dave Loudin
6-Jul-2010, 8:16 PM
Here is my friends report. He lives much closer to the towers and also wants to put something in the attic. Is he out of luck too? What are his options? Thanks in advance.

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d9fbe4ead3d4ece

At first, I want to scream "Are you kidding me?", because the answer is obvious, at least to me. I realize that you're asking because you are not familiar with this stuff at all, and that's OK.

The bottom line: I think your friend could use an indoor antenna, the Terk HDTVi in particular, to get at least 11 stations (and their sub-channels). Why can he do that and you not? Two items to compare between the two reports: Noise Margin and Path

The Noise Margin (NM), specified in dB, tells how much signal is present with respect to the noise level. Zero means the signal can be locked and decoded by almost all receivers. To protect against all kinds of fading, we like to design for an NM of +10.

I would expect you to point out that your top three stations have NMs of over 50 and 30! Why can't you use a small antenna? It's the second factor - Path. For your friend's case, the top stations are all "LOS," or line-of-sight, meaning that there are no terrain obstructions between his house and the transmitters. In your case, most of your stations are "2-edge," meaning that signals have to bend over two obstructions to get to you. As you might imagine, such signals will be more unreliable, so more margin for fade protection is needed. Designing to +20 NM is not unreasonable.

Now, after subtracting for fade margins, we are left with noise margins of 13 to 15 for most of what you want (and still 30 for WRGB). One more thing to consider: losses from putting the antenna inside. Measurements comparing attic to rooftop installations put the loss at 15 to 20 dB in most cases, with a best case of 10. Using the mid-point, we're now down to virtually zero NM. You need the gain provided by the antennas Tigerbangs recommended to get the NM back up for reliable reception.

You can follow this logic for your friend's case to see he can get by with an antenna that has zero to 2 dB gain.

Good luck!

Thinkup
6-Jul-2010, 8:28 PM
Awesome response, much appreciated Dave. I'm a total geek and while this is all totally new to me I'm super quick with new info. So my buddy has it pretty easy and I'm stuck with the harder decision. My only last bit of help I would need is if you know of any more "attractive" antenna designs to go on the roof my my situation. Or perhaps at least something smaller? Is the amount of gain you get from the antenna based in relation to its size? I have an unused dish on my roof from the old owner. I could use that spot but the antenna would have to be smaller.

For the buddy. Would you put that littler terk near the TV or go through the trouble of putting it up in the attic? Or even point it out the window if possible?

Dave Loudin
6-Jul-2010, 8:30 PM
So what I'm looking for is a directional VHF antenna that fill fit in my attic that will give me both low and hi VHF signals then? Is that correct? Is it even worth trying considering the hills around me?

No, you need a VHF/UHF antenna (look at the Real channel column). I was trying to second-guess what you meant about what to skip for a smaller antenna. Elements for VHF reception are much larger than those for UHF. TVFool has already considered the hills for you as far as reception goes at your house. If you are asking about putting an antenna on one of those hills, then use the "start MAPS" option to move the receive location marker to the right spot.

Dave Loudin
6-Jul-2010, 8:40 PM
My only last bit of help I would need is if you know of any more "attractive" antenna designs to go on the roof my my situation. Or perhaps at least something smaller? Is the amount of gain you get from the antenna based in relation to its size? I have an unused dish on my roof from the old owner. I could use that spot but the antenna would have to be smaller.

For the buddy. Would you put that littler terk near the TV or go through the trouble of putting it up in the attic? Or even point it out the window if possible?

What's not to like about that Winegard or ChannelMaster? :) You're stuck with that form, as alternates like bowties and interesting homebrew designs do not handle channel 6 (meaning their gains would be -20 dB or so). For a rooftop install, you might be able to go down one model in the Winegard line to the HD7080. However, Tigerbangs has lots of experience in this realm, so you can trust that what he recommends will definately work.

For your friend, putting the Terk near a window would be best. Just keep it away from things like compact flourescent bulbs and anything with a CPU in it.

kb2fzq
7-Jul-2010, 8:20 AM
If you're looking for a small, powerful antenna, look this over...
http://www.digiwavetechnologies.com/index.php?module=pagemaster&PAGE_user_op=view_page&PAGE_id=281
I use two in phase to get the same channels you are looking to get, it is VHF-hi/UHF. I'm 53 miles from the Helderberg antenna farm. It probably won't pull WRGB, as the channel assignments in the picture are for Australia, not the U.S., but, WRGB is simulcast on 45.3 in SD.
If you're interested, PM me, I'll tell you where you can get it...

baud
7-Jul-2010, 10:29 PM
If you're looking for a small, powerful antenna, look this over...
http://www.digiwavetechnologies.com/...ge&PAGE_id=281

If you want a small footprint antenna that works well this can't be beat at my location by the following list of antennas I've tried.

CM-4228 original
VU-190
HD-7697P
YA 1713

I'm not saying it's better than these but works as well and it is small.

My location
Lat: +43.560205
Lon: -71.012282