OT: How Far HDTV Signals Travel?

[Randy L]

I live in Gulfport, MS and am considering building an extra long range HDTV antenna to hopefully pick up stations in nearby Mobile and New orleans, both about 70 miles away. Since I don't want unsightly antennas poking up above the house, I'd like to put it in my attic.

Do y'all think I'm wasting my time due to the sheer distance? Can't get local channels on DirecTV and cable TV won't be at my new subdivision for at least a year.

[djg]

I get good reception with an antenna in my garage rafters, stations about 30 to 40 miles away. An old radio shack tv antenna, pre HDTV. It's about 10 feet off the ground. I am up out of a river valley, probably depends on your geography, and how high you can get the antenna.

You can get locals if you pay.

[stangbat]

The actual HDTV radio signals travel no further than standard definition analog signals. HDTV is broadcast in the VHF and UHF bands just like analog TV. The difference is the modulation of the signal. Someone else that knows more than me can comment regarding the signal power that is transmitted for HDTV and if there are big differences in reception. My experience with over the air HDTV reception tells me there isn't much difference. If I had trouble receiving the analog signal, I also had trouble with the digital signal because the tower was a long ways away.

Any regular UHF/VHF TV antenna will work with HDTV. As long as an antenna is designed to receive the bands you are interested in, the fact that it is HD or SD does not matter. The tuner (receiver) is what determines if you get digital TV or analog. So what I'm saying is that any good practices for receiving standard analog TV also apply to HDTV.

[Æ]

http://www.antennaweb.org/aw/info.aspx?page=FAQ

[rone]

I live in Gulfport, MS and am considering building an extra long range HDTV antenna to hopefully pick up stations in nearby Mobile and New orleans, both about 70 miles away. Since I don't want unsightly antennas poking up above the house, I'd like to put it in my attic.

Do you get anything at all with bunny ears?

Before spending a bunch of money, it might make sense to make one of the diy 4 bay bowtie antennas to see if it works at all. If you see an improvement over bunny ears it might be worth building a better one.

Antennaweb.org says you will only get 4 stations, but it is fairly conservative.

http://www.hdtvantennalabs.com/location/39507/ gives a list of likely channels and a suggestion for a setup

[billfitzmaurice]

Do y'all think I'm wasting my time due to the sheer distance? Can't get local channels on DirecTV and cable TV won't be at my new subdivision for at least a year.

Possibly. TV transmission is basically line of sight. That's why transmission towers are so high, and antennas are roof mounted. The good news is that you don't have any mountains in the way.

[spasticteapot]

There's a good chance that all of your TV signal is being broadcast from a bunch of relatively close transmitter antennas - possibly even the same one. If this is true, you can buy or (preferably) build a highly directional antenna that will give you greater signal strength and less noise without any electronic filtering.

[marvin]

Randy,

Denny's Antenna Service is a good source I have used for information and purchase.

http://www.dennysantennaservice.com/

They offer guaranteed satisfaction, money back if not satisfied, shipping is included in listed prices, and a useful online recommendation tool specific to your location.

They offer some well made custom designs of their own, too.

http://www.dennysantennaservice.com/...v_antenna.html

In my location only 20 miles from Chicago's towers, leafy trees ahead of the antenna have been the biggest problem on windy days. No problem during the winter when the leaves are gone, but when they grow out in the spring, they reduce the signal a little, but can make it unusable when windy.

Placing the antenna in your attic will cost you some signal, but a good antenna and amplifier may compensate. Put it on the roof if you need to, but then you need to add ground cable and rods

Over the air 1080i is a nice picture, often better than compressed cable HD signals.

Marv

[fbov]

I would ask that question here:
http://www.avsforum.com/avs-vb/forumdisplay.php?f=25

[Ron_E]

I live in Gulfport, MS and am considering building an extra long range HDTV antenna to hopefully pick up stations in nearby Mobile and New orleans, both about 70 miles away. Since I don't want unsightly antennas poking up above the house, I'd like to put it in my attic.

Do y'all think I'm wasting my time due to the sheer distance? Can't get local channels on DirecTV and cable TV won't be at my new subdivision for at least a year.

I was told by a tech that used to work for the Public TV system here in Iowa that putting an antenna in the attic really cuts down on signal. I have an antenna (small RS uhf/vhf) under the roof which is a good thing with wind and ice storms. It works pretty well but I'm only about 15 miles from the antennas.

If you haven't done HDTV OTA you'll find it's not like analog. You could watch weak signals with the analog system. You'd have noise and ghosts and stuff but you'd have something. OTA HDTV is pretty much all or nothing. Bad weather will cause drop outs and no signal problems with my setup.

Ron E.

[WWWJD]

My favorite web site for this kind of stuff is tvfool.com. Their interactive google maps are pretty useful for figuring out signal strengths based on elevation and geography. Clicking on the bubble next to the station of interest brings up a signal strength plot for your particular location.

Just a quick look at Gulfport; Mobile or New Orleans (over the water) might be your best bet for obstruction avoidance; you've got a mix bag of stuff around you. You've got ABC and FOX to your north, while the nearest NBC affiliate is out of New Orleans, and the nearest CBS affiliate is out of Mobile.. three different headings on the compass. (Ewww)

I'd probably do a high gain model, and try aiming it right at New Orleans; they've got a good cluster of stuff in the same spot even though it's on an extreme fringe.

Or... you could go HD Gold on Dish Network and get the locals in HD like me. I hung an antenna before I signed up and found out that I wasted my time with the whole antenna thing. The only thing it's good for now is roosting birds.

This is the one I went with; mounted on the roof with an old Directv dish mast. Light weight, low wind load.. I've got no complaints and I'm getting stations out of Indiana whilst being pointed in the wrong direction. Honestly dude, it really is an all or nothing crap shoot, but I can tell you that attic mounting destroys the signal for everything but stations in the range of 10-15 miles.

[moosespeaker]

Randy

Just as us "nuts" design/build speakers here there is a similar group DEVOTED to UHF antenna design. Most builders are in Canada where there try to get signals from US cities; nutty regulations on getting HBO for example.

http://www.digitalhome.ca/forum/forumdisplay.php?f=186

They have their antenna design simulator programs. Their main designer goes by 300ohm (impedance of TV twin lead); he is in New Jersey.

I started building one design but found a better way to get my local high def channels (thanks Froste!).

I have a partially completed single bay antenna (+ 16dBi). PM me if you would be interested in playing with it. The reflector array is done and would need about 2 hours of work to get active elements bent. Hate to throw it out!!!

George

[benchtester]

I have found these two web sites very helpful:

For determining reception:
http://www.tvfool.com/


For comparing antennas:
http://www.hdtvprimer.com/ANTENNAS/comparing.html

[Randy L]

Thanks all. I'll check those sites and links. I bought a couple good HDTV antennas from Wal Mart ($20 & $40) and both recieve very well to perfectly for the ABC and Fox channels we can get here locally. The ABC channel is 30 miles away and it comes in at near full strength.

Beside the house is a really big tree; maybe I can mount it on the tree (20 feet up or so) to maximize reception chances.