Picture of Build a Large DB8 HDTV Antenna: Big Bertha
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We've had Cable TV and Cable Internet. It seems that there is less and less on cable than there ever was. Cable in my area is $49. I eventually cut down to basic for $20 and supplemented with Netflix. Netflix is excellent by the way but that's another story. We also have my macintosh connected to the TV so we can Hulu any program that played recently.

I'm finding that even basic cable has little 'value'. By value I mean I get the basic local channels and a bunch of junk otherwise. The channels I look at I could get for free if I used an antenna. Hence, I've decided to minimize.

Here in Southern Maine the TV stations are mostly in Portland about 30 miles away. Some are further, about 50-60 miles away. Most HDTV antennas work for 30 miles and a few claim to get up to 60 miles. I decided that I need more antenna than that. Something where 60 miles might be the limit but a doable and good limit. I've decided to produce a DB8. A DB8 antenna has 8 receiving elements, or 4 pairs of elements. It's basically two DB4 antenna's combined. The last picture in the segment is a commercial one.

What follows is my foray into the world of HDTV antenna construction and trying to squeak the most out of it for a moderately fringe TV area I live in.

BTW, the last segment contains all kinds of HDTV signal information and links to places to assist you in learning more. I was a teacher for 30 years (no I don't want any help with my grammar, I said I used to be a teacher) My job was simplification and clarity. I hope this instrucatble is up to that.
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Goofus521 month ago

In making your whiskers you used 6 gauge wire. I have a bunch of surplus solid 12 gauge wire laying around, so would it be the same if I braided to 12 gauge wires together to make each whisker? I know it'll take a little time but in this case, time is cheaper than money.

deceiver (author)  Goofus521 month ago
I only used heavier wire so that It wouldn't sag, or bend over time. I suppose you could twist a couple of 12's together. It would probably be pretty resistant to bending. It shouldn't affect the signal any as far as I know.
mtsav8or1 month ago

Thanks for posting this build. It answered a lot of questions I had about connecting multiple antennas to create an array. What are your thoughts about connecting two antennas facing in opposite directions? My closest stations are positioned almost 180 degrees from each other. I know I could add a rotor but I'm looking to setup a DVR system and want to record channels from both directions at the same time. I haven't tested an Omni directional but I'm in WV and live in a valley with 400 feet of hills in all directions.

deceiver (author)  mtsav8or1 month ago
Yes you can. A digital antenna mounted on top of each other pose no interference issues with the other antenna. A rotor is an option but it you want two antennas and the stations are 180 degrees from each other then you'd never have to move them.

If on of the stations are close compared to the other maybe a smaller antenna might work in that direction. If that's the case it would save a lot of work and expense. Remember the digital signal will either be on or off. No snow or weak signal issues like VHF used to be. If you get it then it's good.

Not sure if you can help me. Am trying to get rid of cable, and purchased two Leaf50 HDTV antennas, which get signals up to 50 miles away. With the Leaf50, I get the basic channels I wanted, except for NBC. NBC broadcasts from 70 miles away. Is there some way I can enhance these Leaf50's so they can get a signal from that far away? I don't think some kind of antenna outside, on the roof, or in the attic can hook up to both tv's of mine (1 upstairs in the living room and 1 downstairs in the family room), right? Please write me back at Thanx!

deceiver (author)  laura.brown.3557441 month ago
70 miles is the absolute limit unless you are up high. Digital TV is line of site pretty much. Higher up and you can do further because you can get beyond the ground level curvature of the earth. Your leaf antenna is a good indoor antenna but not like one of the larger roof mounts. When you see reviews of any antenna you'll see people who love them and those who hate them. The reason is that someone in the middle of a city where all the stations are, will get a signal for 50 stations with something very small. While others with huge antennas but living far from stations will think it doesn't work. Yours is good for signals maybe up to 30 miles away. 50 would be pushing it.. unless you're up very high. You can put this antenna or one on the roof hooked up to two tv's. You just need a splitter (radio shack, walmart a few bucks) You lose a couple of decibels of signal but it does work well. Too hook it up you connect the coaxial cable into one end of it and there's two connections on the other side of it that go to each TV. A larger antenna, mounted fairly high up on the roof with a splitter and maybe a mast mounted amplifier 'might' get what you want. It all depends on the terrain (mountains?), distance to the station, and another factors is how much power the station is transmitting with. There are links at the end of my instructable that will let you type in your zip code and it will tell you the possibility of tuning these stations in. It takes into account the topography of the land, asks you how high you'll mount it, and a bunch of other factors. It is pretty accurate actually. Good luck with this. The other option is to have a smart TV and get a service like HULU that lets you look at last nights tv programs the next night. It works well and is about $8/month. Let me know what you end up doing and if you have any luck with it. If something isn't clear here please don't hesitate to ask for clarification.
Ray.P.Waddell4 months ago

Is 19ga 1/2" hardware fabric good for the reflectors?

deceiver (author)  Ray.P.Waddell4 months ago

yes, as a matter of fact that's what I used. it's 1/2" squares of galvanized mesh. Anything's okay as long as it's no more than 1" square mesh. And of course any solid metal would probably be taken out by the wind.

The mesh you're talking about is still bendable but stiff enough to last the test of time. And being galvanized is important in the weather but won't affect the signal at all.

john.wraith.56 months ago

This is definitely one of the better home built antennas, I am currently building one similar to the DB8E on a PVC frame and can tell you have done the research on this.

one small comment though , I think you meant to say cut the wires at 19 not 18 ( unless i am not understanding correctly)

One thing I havent found any info on the whiskers being swept forward increasing directionality, also when making an array did you come across any info on the distance between them?

Outstanding job on both the antenna and instructions

deceiver (author)  john.wraith.54 months ago

You're right about the 19" instead of 18". Thanks for pointing that out. The reason for the bent whiskers and background signal reflector is that if the reflector and whiskers are flat, the reflector will reflect the signal directly to the back of the whisker. It would only have to be the width of the whisker.

By raising the whisker higher above the reflector and tilting it forward, the reflector can be made larger with more area reflecting onto the whisker. Think of it this way. The further you move the whisker away from the mesh, the more it begins to act like being closer to a focal point.

Now, this isn't a direct TV reflector! There's a point of diminished returns. If the whisker is an inch above the reflector then flat is good. A little higher lets you add more reflector maybe getting more signal to the antenna collector (whiskers).

vuk658 months ago

Great Job! Did you try only one antenna before you set up the array to see if it made a difference? Also, I would like to put mine in the attic. Can I use foil sheet on cardboard as a deflector? I have already made an antenna but I really like your design!!

deceiver (author)  vuk658 months ago
Tried only one smaller one.
out of the wind anything metallic should work.
Dano6698 months ago

I am on a hill, on my street. It is 139miles to Boston from town. My LOS is not real good, unless Boston is more direct across the water. I know driving down I295 there is a nice hill, about 295' elevation. I do believe that I am on a high point in town though. The humidity is having a factor in it as well, normally can get most of the station down there at 75% or better, when we are about 50% humidity.

deceiver (author)  Dano6698 months ago
A hill of that height would be like having an antenna mast that high. Low humidity is better. The more moisture in the air, the more the signal is absorbed. 139 miles is a long ways. Even an elevation like yours doesn't seem high enough to overcome the earth's curve. Are you sure it's Boston? I'm 90 miles from Boston and can't get them.
Dano6699 months ago

Hello, I am also in Maine, South of Augusta. I was wondering how high you have your antenna and which stations you were picking up? I recently paired up a couple of 8-bay antennas and now find myself receiving a lot of Boston channels on top of those from Maine. I was wondering, if it was something to do with the weather. Not sure how much longer my DX-ing will be going for, I hope a long time.

deceiver (author)  Dano6698 months ago
Weather only hinders signals. It wouldn't help. I'm impressed that Boston stations would come in. You're what, about 200 miles from Boston. The only way that is physically possible is if your elevation is very, very high. Anything over 70 miles, line of sight at sea level should not be possible because of the curvature of the earth. The distance to Boston form around Augusta is only available with a good antenna and elevation. Bravo for you if you have that situation.

If you are then the Maine stations are pretty much on the coast in line with Boston.
Wooodyii29 months ago

Hello again, Is a splitter and a combiner the same thing? I have seen splitters at the store with 1 input to 2 outputs, but nothing 2 inputs to 1 output. How much roughly do you think the antenna itself cost you? Lastly, would drywall corner bead be good enough for the parameter of the antenna or is the aluminum angle the way to go?

deceiver (author)  Wooodyii29 months ago
yup, splitter/combiner is the same.

I've seen stiff and very thin drywall corner bead. You'd have to judge yourself depending on what you find.
Wooodyii29 months ago

Hello, and great write up. I will be making 2 of these within the next week and both will be twin arrays. Is there any thing you would have done any differently for better signal or is this pretty much the pinnacle of the design?

Sorry, one more thing. The distance from the antenna to my tv is probably going to be about 40 to 50 feet. Is there any other steps or details I should be aware of because of the distance? Thank you

deceiver (author)  Wooodyii29 months ago
There will be a slight loss with longer cable. check it out and if you're not getting the stations you expected to then an antenna amplifier would help. If everything works okay though, why the added complexity and cost.

Thanks for the info. Stainless it is then.

deceiver (author)  Wooodyii29 months ago
Actually no. I probably would have mounted it a little higher if I could. I might have forgone the rotor as i don't seem to need it with stations almost in the same direction. I'm fairing well so far but to do it again and some day I probably will do this. I'd splurge for some stainless steel screws/bolts and such especially where wires connect.

Good luck.
rambler5011 months ago

I made 3 of them 1 for me 2 for a friend. They do a great job, they look very professional.

deceiver (author)  rambler5011 months ago

I'm so glad it worked out for you. My antenna is still working great after all these years. That, with cutting the cable, amazon prime, hulu plus, and a mac mini downloading other stuff and we're very happy with our entertainment bill with only internet being payed for.

deceiver (author)  deceiver11 months ago

Hey, post some pictures huh?

An updated link for the diagrams
Oh, yes forgot to mention since it was going in my attic, I made mine out of 1/2" PVC pipe for the frame, and an aluminum window screen for the reflector. The array mount was a 3" wide piece of pine. I used 45 degree connectors which I sawed "nearly" through and bent out to the right angle
I built this and boy does it work great, even in my attic!

Since I live in an area where there are a few channels in the high VHF range I modified the antenna a little so that the last pair of wiskers are were cut to 29" and bent to 14.5 V 14.5.

Since the focus for those frequencies is further out, I also made the piece of wood that the antenna array is on sit at an angle to the reflector, with the top of it about 6", and the bottom out about 15".

It's best to experiment with the distance from the reflector gets the best signal by moving piece of wood around while you have a TV attached till you get all the channels you are looking for.
where did you get this plan from. or is it of your own design.
thank you
if you made four (two in a set) and put them on either side of the house could I get better signal?
deceiver (author)  Firewire Pro2 years ago
Yes, more collection area the better the signal. But... if you're getting all the stations within line of site with one segment or two then adding more won't help. With digital you either get the signal and see a picture or you don't. So, a good antenna will see what it can see from what is being sent to it. If a station is behind a mountain then it doesn't matter how big the antenna is.
jrbilodeau2 years ago
Not sure if i missed it, but how far away did you mount the reflector from the whiskers?
koda572 years ago
I built one of these antennas , thought i would have to build the set of 2 because i wanted to pick up fox which is about 50 miles away ( the way the crow flies ).
However the one ( 36 x 40 ) did the job.
louisrosa2 years ago
wow--what a workshop. you could make anything in there. congratulations on the instructable, the pics are great and the antenna fine. i really like the ship however
jmiller902 years ago
I have an old home with a basement full of old window screens. What do you think about using the screens as reflectors? I too am trying to cut the cable. Thanks for your ingenuity.
deceiver (author)  jmiller902 years ago
I'd not think so. First the screen has to be metallic. If it is okay but then if you've ever walked with screens on a windy day while putting them in you've noticed that they can act almost like sails. The screen would wobble the antenna and disrupt the signal. They might also come down in a big wind too.

The wavelength of the antenna is such that any mesh one inch or smaller will suffice. The 1/4" mesh I have is fine, 1/2" would have been just as good. A few feet of a roll at a hardware store is only a few bucks and is stiff so that it mounts good and is durable.
Hamosia2153 years ago
Anyone ever try to make 3 or 4 of these and combine the signal? Any thoughts or advice with this idea? Also stacking them vertically doesn't have any negative effect on the signal? Thanks for your reply!
Stacking vertically makes the signal reception swath VERY narrow. Horizontal stacking is better for most issues, but they must be perfectly balanced. If your coax lines are even 1" different in length to the combiner you will get signal loss.
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