Anyone ever build a homemade antenna?

The TV antenna that you see is not a true Yagi. It is a modified " Log-periodic" where the releflectors and "active elements" alternate left and right sides, are of variable length, and thus is of wide band or broadband reception, and is of nature directional. It is difficult at best to scratch build. The next best design might be the discone which is easy to build (sic). If you only have one station in mind, you could build a yagi on that frequency, but I think you want to get all available, right? Another problem with television, is that the frequencies are not in the same band. See the wide band nature below.

VHF Band - Ch. 2 - 13 ; 54 - 216 Mhz
Low Band - VHF Ch. 2 - 13 ; 59 - 88 Mhz
Mid Band - UHF Ch. 14 - 22 ;121 - 174 Mhz
UHF Ch. 95 - 99 ; 91 - 120 Mhz
High Band - VHF Ch. 7 - 13 ;175 - 216 Mhz

IMHO, I would try a newer used commercial antenna, aimed at the city of interest, or a discone at reduced signal gain because of its omni directional design.

L

Take a long wire, strip about two inches and wrap that around the whip. Helps sometimes.

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I'm a die-hard DIYer and a ham radio operator, but for a TV antenna I'd jump on the 'buy it' bandwagon. You can probably find an old antenna pretty cheap or free, and if it's in good condition it should still work just fine. Or, buy a top quality new one for under $100. As mentioned channelmaster and winegard both make a wide variety of excellent antennas to suit any situation.

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TV antennas are that expensive/hard to get right eh?

I found a tower and an old antenna on freecycle. Still going to build the one that I said earlier. At this point, I just want to do it and see how it does vs. the one I am going to get off of Freecycle.

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I watched the video and wrote down the parts and directions. I will post the text and make up a picture to show you.

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Plus, I'll try to do it this weekend.
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Supplies.

6 wire clothes hangers
12 washers and 12 wood or drywall screws
2 1/2 to 3 foot piece of 1 x 2 board.
Tape Measure/Ruler
Cordless Screwdriver
Sandpaper or knife
Pen/Pencil
Pliers with wire cutter
Section of Coax Cable with ends
Balun, also called a UHF/VHF Transformer (radio shack)

Cut off the heads of the coat hangers and bend the remainder into straight pieces.
Cut these into (8) 14 inch pieces. This will leave 2 long pieces remaining from the 6 hangers.
Clean off the center sections of the 14 inch pieces until you have bare metal.
Measure 2 inches down from the top of the board and mark it.
Measure 5 43/4 inches and mark on each sides of the tape measure.
Measure another 5 3/4 inches and mark each side again.
Measure once more to another 5 3/4 inches and mark each side again.
Put x's on each mark
So you have 4 sets side by side

Take one of the long wires and bend it.
Start at the top mark on the right.
Move to the 2nd mark on the left
Again to the 3rd mark on the left
And then bend back to the 4th mark on the right
Mark the wire at the 4th mark and cut it off
Use this one as a templete and bend the second long wire.
On both long bent wires clean off the ends
and also each bend to the bare metal
And then a section directly between the 2 bends.

Bend the 14 inch parts in the middle at 7 inches.
The ends of the V should be about 3 inches apart when bent
Take a V and secure it with the screws and washer at the top
right mark. Put one of the long sections under the v and tighten really good.
Cross over to the 2nd left mark and then 3rd left and then 4th right.
Do the same with the opposite.

Attach your uhf adapter to the center V's .

Wow, thanks bnlfan,

That's great. I wouldn't have caught the crossing from the other blog... I mean he talks about it, but it's not clear where it crosses.

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Looks like it should work on UHF stations....

One thing I noticed in the drawing is the feedpoint is at one of the middle dipoles, I think it should be centered between them. Might check the original design.

By the 14 inch dipole affect of this antenna it would be UHF channel 14 and up

Feed point does not matter "that much " recieving. Critical transmitting.

Just 2 more cents

L

It does... the top and bottom halves only sum at the center. A feedpoint as shown will subtract the top from bottom halves. If the feedpoint had to be at one of the dipoles, a center wire crossing is needed.

Maybe you were thinking of impedance matching....I agree that the match is less critical on a receive antenna.

The devil is in the details

About 15 years ago we had a work crew that was living on site. They were so bored they decided to do anything they could to get reception. They found an old metal frame in a trash pile. This was the precursor to the box springs, back when it was only the metal with no covering. Somehow they got it into the top of a tree and ran the antenna wire up the tree and hooked to the springs. They got excellent reception!

A friend gets excellent reception on a short wave radio by using some automotive wire ran up a tree, then in the window. She put an alligator clip on the end of the wire and clips it to the antenna of the radio.

Sometimes the weirdest things work very well.

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I'm not trying to take over this thread but these posts reminded me of something that happened not to long ago.

I was at work with some down time and I decided to make some stablizers for my canoe. I had the parts in my van and brought them in to work on. After I finished someone made an off handed joke about them.

I asked them to tell me one thing that is produced in this world that did not originate from some "redneck" (has to do with their comment) who had a need but not the money to either buy the current item or it wasn't being made yet. Everything we have started out as several of something else's modified to make one of whatever the need was.

American Ingenuity. :0)

What Gary said.

I've built a number of antennas for various applications when I was younger and had time to burn.

You need a simple dipole antenna centered on each band. If you want to start building an antenna with gain, things get tricky real fast, and you will be much better off with a commercially built antenna.

Gain is a bit of a myth. The more gain an antenna has, the more directionally sensitive it is. It doesn't mysteriously suck more signal out of the the air, it simply concentrates more on a signal coming from a certain direction. This means you need a way of pointing your now directional antenna, usually by means of a rotor.

Save yourself the energy of trying to fabricate some claptrap antenna and rotor and find someone on freecycle giving a vastly superior product away for free.

Pete