Help needed choosing an antenna

[Bud]

Hi, I'm completely new to all of this. Not sure which antenna will work or if I'll need a booster or what? I'd love any input on a good setup to reach about 80 miles. Right now I'm getting about 13 channels on an old VHF/UHF antenna mounted outside. I'm about 70 miles east of Baltimore and Washington, the Chesapeake bay is between here and there. It's dead flat around here not much if any elevation change. I'm going to mount the antenna around 25 ft up but that's not set in stone. Also my house has a metal roof, dunno it that messes with anthing or not. Not sure what other information would help. Thanks in advance!

Here's the link for my report:
http://www.tvfool.com/?option=com_wr...f1f07be9604f6c

[rabbit73]

I think you are doing pretty good with what you have.

What channels are you getting now?
What direction is your antenna aimed?
How high is your present antenna?
What channels do you want at 80 miles?
Any trees in the way?

[Bud]

Thanks for your time. I'm getting 16-1,2, 21-2, 28-1,2,3, 47-1,2,3, and 64-1,2,3. The antenna is aimed due south about 16ft up with no trees within about 600ft any direction. I'm trying to get an NBC channel from anywhere, the closest(74mi) is in Baltimore. Any other channels will be a bonus. I remember as a kid my dad had an antenna that we could get DC, Baltimore, Norfolk, and Philadelphia channels from about the same location as I am now.

[Tim]

WRDE-LP on 31 is an NBC station. It is in a completely different direction from your other stations. You could probably use an antenna such as the Antennas Direct 91XG pointed at 88 degrees. Feed it with a separate coax line and use an A/B switch to swap between your antennas. Depending on the length of your coax, you might need a preamp.

[Bud]

Tim, for whatever reason nobody around here can seem to get 31.

[Tim]

Is anyone around there using a high gain UHF only antenna and a preamp in the attempt to receive it? The other NBC affiliates on your TV Fool report are much weaker. Using the 91XG I receive a low power station in my area that has a little lower NM than your channel 31. Of course, your results may vary.

[rabbit73]

for whatever reason nobody around here can seem to get 31.

That's odd. I thought that Tim's suggestion was a good one, because that station is listed as active on rabbitears.info and WRDE has a website.

http://www.rabbitears.info/market.ph...&callsign=wrde
http://www.rabbitears.info/search.ph...pe=dBm&height=

Wikipedia has an article:
http://en.wikipedia.org/wiki/WRDE-LD

WRDE has a website:
http://www.wrdetv.com/

Contact INFO:
http://www.wrdetv.com/index.cfm?ref=30100

CONTACT WRDE TV
17585 Nassau Commons Blvd Suite 3
Lewes, DE 19958
Phone (302) 227-WRDE (9733)
Email news@wrde.com

Why don't you call the station engineer?

I see you are in the Blades area. My wife and I used to take the Lewes ferry to Cape May for vacations.

Coverage map in attachment.

[Bud]

Tim and rabbit73, I'm not sure what anyone else is using but I doubt they've put much research into it. I'm just learning about this stuff myself. I just assumed that 31 was a very weak station that was just serving the beach area. I would like to avoid an a/b switch and a second antenna just for the sake of convienence. I looked at the antenna you sugested and some others on their site. Do either of you think a DB4e would do what I need? I ask because it can be aimed two different directions. Also I have no idea what pre-amp I would need to use, I think I read somwhere that you can go too strong and lose reception on some channels?

Rabbit73, I've lived here my whole life and oddly enough have never made it over to Cape May. I guess you don't notice what's in your own back yard lol. It is on my list though.

[Tim]

Originally Posted by Bud

I just assumed that 31 was a very weak station that was just serving the beach area. I would like to avoid an a/b switch and a second antenna just for the sake of convienence. I looked at the antenna you sugested and some others on their site.

Channel 31 is weak at your location hence the need for a high gain antenna.

[Bud]

Do you think the DB4e has high enough gain to get 31? I see it's 2.2dBi less than the 91xg. I want to run 2 tv's off of this. The run to the 1st tv and splitter will be about 40ft and then about 30 ft from there. Any suggestion on a preamp?

[ADTech]

Before investing any money in trying to get WRDE, invest a few moments of time and LOOK in the direction of that station. What do you see? In other words, what does the view, and consequently, the signal path, look like as seen from any potential antenna mounting location? Take and post a photo, if you can.

In general, if you have a nice, clear view out several hundred yards or more, reception should be feasible. The opposite condition, where you're staring point blank into a forest, a big tree, your neighbor's two-story house, or whatever, means very poor odds of reception success.

for whatever reason nobody around here can seem to get 31.

Either they don't know about it (WRDE only recently, '09 or so, became an NBC affiliate) or your neighbor's directional antennas are facing the wrong direction causing that signal to be rejected.

Just be aware that WRDE is only a 7100 watt transmitter on a 300' tower. Don't expect much of a coverage area, especially beyond 20 miles.

[rabbit73]

I just assumed that 31 was a very weak station that was just serving the beach area.

That might be true, but you don't know unless you try it. The tvfool report indicates it is possible, IF you aim an antenna its way at 88° magnetic.

for whatever reason nobody around here can seem to get 31.

Their tuners might have been overloaded by WBOC.

I would like to avoid an a/b switch and a second antenna just for the sake of convenience.

Of course you would, but it would be less trouble than swinging your single antenna around for CH 31. And it would be less trouble than trying for WBAL. The problem is that your stations are in different directions, and the antenna must be aimed at the transmitter.

I'm trying to get an NBC channel from anywhere, the closest(74mi) is in Baltimore. Any other channels will be a bonus.

I'm taking you at your word; didn't you mean it?

One possible solution to avoid the A/B switch or rotator would be a DB4E aimed at 31 connected to a separate tuner. The A/V output of the tuner would go to the A/V input of the TV. You would switch antennas by switching the input switch on the TV.

I remember as a kid my dad had an antenna that we could get DC, Baltimore, Norfolk, and Philadelphia channels from about the same location as I am now.

That was in the days of analog TV, when we could tolerate a little snow as the signal got weaker. Digital TV is different; it's all or nothing as it gets weaker.

Do either of you think a DB4e would do what I need? I ask because it can be aimed two different directions.

The DB8E, not the DB4E, can be aimed in two directions, but it doesn't always work.

Also I have no idea what pre-amp I would need to use, I think I read somewhere that you can go too strong and lose reception on some channels?

What you read is correct, your strong signals would cause overload of the tuner or a preamp.



Interpreting Noise Margin in the TV Fool Report
http://www.aa6g.org/DTV/Reception/tvfool_nm.html

WBOC is already at 68.8 dB NM. If you add the antenna gain of the DB4E, about 11.5 dBd average, you are at 80.3 dB NM, without even adding the gain of a preamp.

Trying for WBAL NBC would be even more trouble. It is on VHF real channel 11, which would require a separate high gain VHF or a VHF/UHF combo antenna aimed at 323° magnetic, a UVSJ or 2 in series to block the UHF signals, a preamp, and another UVSJ to combine it with your UHF antenna. An alternative to the UVSJ/UVSJs before the preamp would be a custom (expensive) single channel bandpass filter for channel 11 between the antenna and the input of the preamp, but that would limit that antenna to only one VHF channel.

http://www.hollandelectronics.com/ca...-Diplexers.pdf

http://www.tinlee.com/bandpass_filters.php?active=1

[Bud]

ADTech, here's the view from where I would like the antenna about 25 ft up(doesn't have to be here). My neighbors house is about 200 ft away and the woods are about 200 ft beyond that.


Rabbit73, thanks for all the info! I'm trying to digest all of it as I'm admitted novice here lol.

Also, Thanks to everyone for the help it is greatly appreciated. I just need to wrap my head around the information and make an informed decision.

[rabbit73]

I'm trying to digest all of it as I'm admitted novice here lol.

I'm still learning too, Bud.

Thanks for the photo that ADTech requested.

It's dead flat around here not much if any elevation change.

The antenna is aimed due south about 16ft up with no trees within about 600ft any direction.

here's the view from where I would like the antenna about 25 ft up

Nice photo, but UH-OH, could it be higher? Trees really mess with UHF signals.

The hdtvprimer site is down now, so no images. Text from Google cache.
http://www.hdtvprimer.com/antennas/siting.html

Trees and UHF

If a tree loses its leaves in the fall, reception behind it will improve dramatically. Many people get a TV for Christmas, and erect an antenna for it in January, and then wonder why it quit working in May. It’s the trees.

In the following simulation, a tree is modeled as a perfect sphere blocking 90% of the signal.

(image missing)

If the antenna is behind a tree, it is in overlapping fields: a weak field that passes through the tree plus a weak field that is diffracted around the tree. Overlapping fields are complicated, with strong spots and weak spots. This will be true even if the tree is not a perfect sphere. If you get a UHF antenna to work behind a tree, you will likely see dropouts when the wind blows because the strong and weak spots will move around as the tree deforms. Even in a good-signal neighborhood it is inadvisable to put a UHF antenna behind a tree.

The farther away a tree is, the less of a problem it is. For far away trees, assume no signal penetrates the tree, and reception will be by diffraction around the tree. Trees block 100% of satellite signals.

[ADTech]

The hdtvprimer site is down now, so no images.

It appears that the domain registration has lapsed. Ken Nist hadn't updated it since back in 2010 or so.

[Bud]

Rabbit73, how much higher do you think?

[rabbit73]

It appears that the domain registration has lapsed. Ken Nist hadn't updated it since back in 2010 or so.

Sorry to hear that. It has been a very useful resource for me and an ideal site to send posters to. Wish I had downloaded some of his images.

Oh, wait, I found one.

[rabbit73]

Rabbit73, how much higher do you think?

I'm not sure. My dumb answer would be as high as it needs to be to get good reception, but that's not a helpful answer.

It wouldn't do any good to enter different heights in a tvfool report, because it doesn't take vegetation into consideration.

Why don't you try it at your planned height to see what you get and let ADTech give you his opinion. If it doesn't work at 25 ft then you will have to decide how important NBC is to you in terms of effort, time, and money to go higher.

[Bud]

LOL, I figured that would be the answer! I'll set it up at 25ft with just the antenna and see what happens and go from there. Now I guess my question is still which antenna the DB8e, the 91xg, or something else? Has anyone had luck with one or the other in a similar situation? I don't mind spending a couple dollars more for a decent product that will last, any preference in brand?

[rabbit73]

I will defer to ADTech for a final answer, but my opinion is the DB4E. The DB8E has more gain, but in a non-uniform field (because of the trees) a 4-bay antenna sometimes beats an 8-bay because it has a smaller capture area. An advantage of the 91XG is that you can tilt the front up slightly, to aim it at the top of the trees.

He might say if you can't get above the trees, forget it.

I hope you realize that we are now in an experimental area with no guarantees.

I like the Antennas Direct products because they are well made, they stand behind their product, and the DB4E doesn't have whiskers sticking out to poke you. Naturally, ADTech would favor his company's product, but he has enough integrity to recommend the best antenna for the job no matter who makes it.