Instructables
Picture of Homemade TV antenna
This TV antenna is not only omnidirectional, but also compatible with the new digital television. I actually get more stations with the new digital television signals than the old system. I get 35 channels and I an a long way from any large city. Some of the stations are over 60 miles away.

Construction is simple using copper tubing, PVC pipe and minimal tools. Tools include a hack saw, drill (hand or electric) screw driver and tape measure.
 
Remove these adsRemove these ads by Signing Up

Step 1: Making the antenna step 1

Picture of Making the antenna step 1
Start with some 3/8 or 1/2 inch copper tubing. Bend a half circle in a 26 inch diameter with an additional 1 inch extra on each end. Flatten the inch on the ends and bend them OUT. Now make another half circle and bend the ends IN.
1-40 of 79Next »
Louie194012 days ago

I am experimenting with this design with materials I have on hand and getting good results. I'm about 40 miles from Atlanta stations, I have only one semi-circle of bare steel fencing wire (#9 gauge) without a transformer, it's up about 12 feet, signals are blocked by large oak trees and still I get great reception of 58 stations. One station that I really want is GPB channel 30, but can't get it yet. Any ideas why? I plan to add a second loop and the transformer to see what happens. Does the transformer just combine the two opposing currents from the antenna halves with some magic to produce a single signal? Anyone know?

rbodell (author) 1 month ago
at 40 to 50 miles they should blast in there unless there is a mountain between you. I once put one of these up to replace a brand new Radio shack 150 mile antenna on a 40 foot tower and it got twice as many stations.

Since everything else seems in order that older coax is probably the next thing.

I am now getting 4 channels from greenbay which confuses me because for a brief period of time yesterday I had 6 channels from wausa which is sort of the other direction. I went higher when the antenna and lost the 6 wausa channels but now I get the four greenbay channels which I was't getting before. I don't understand why I would lose channels going higher. Could turning the antenna have any effect as I took it down when I made the mast longer and it may therefore not be facing the same way it was before. Thanks again for all your help ad advice.

rbodell (author)  arlen.burgess28 days ago
There could be a slight directional capability in a borderline situation if the two splits in the two halves of the antenna are lined up with a station, but it is small and generally non-directional.Try turning it 90 degrees and see what happens. If the two halves are lined up with a station, a 90 degree turn would make the weaker station better.

Update I checked my connections and one of connectors from the transformer was very close to the copper tubing on the other side so I loosen the bolt and turned the connector away. Now I am getting some stations but just barely if I hook up a little tv directly to the coax that comes down from the antenna. The longer runs of coax to my tvs in the house are weakening the signal too much to get anything at all. I tried to use an amplifier that plugs into the outlet and has a coax connection for in and out but I get no signal at all with it. Any ideas besides prehaps going higher yet with the antenna?

rbodell (author)  arlen.burgess1 month ago
I guess the size of the cable could have something to do with it. I don't know how long of a run you can make with smaller cable bit I can't imagine what the max distance is. I have run it 150 feet without any noticeable loss. that doesn't mean anything because I am no expert here.

Are you sure about the distance to the transmitter? I have gotten stations way over 100 miles with it on flat ground and the antenna above the trees.

Pardon me if this sounds silly, but do you have a converter box if you are using an older television?

On longer distances higher antennas work better. Preferably above surrounding trees in the direction of the station.

.

Thanks again for your help. I went higher with the antenna but I think the coax cable I used to make sure I would have enough to get down to the ground is bad and/or the female to female coax adapter so I,m going to go back to using just the coax I started with as it is brand new. The transformer which is a outdoor matching transformer is also brand new. Here is a link to the report for my area on tvfool.com http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3dec2f31a9f0a7fe I guess I misspoke in my earlier post it looks like a number of the towers are 40 to 50 miles away. I do not have a converter box but I am using newer tvs bought in the last 5 years or so, so I do not need one. I am sure there are people out there who might forget about needing one though with an older tv. Thanks again so much for all your help.

Hi All,

First of all let me say thank you to rbodell for making this instructable. I made this antenna and so far its not working for me. I am probably 60 to 70 miles from the nearest towers. I have the antenna on my roof so it is probably 35 ft or so up in the air. How close to 26" in diameter should it be? Does it need to be really close to round? Mine is much closer to an oval. I have tried amplifying it but still when I make my tv search for channels nothing happens. I would appreciate and advice any of you guys can give me.

Thanks,

Arlen

rbodell (author)  arlen.burgess1 month ago
This antenna is very forgiving. I have had people build it without a tape measure and just guess at the measurements and they worked good.

My guess is that there is an electrical connection between the two halves of the antenna. There should be no connection between the two contacts of them
rbodell (author)  rbodell1 month ago
You might also check for continuity between the two wires of the lead in cable. The only other thing is that some people forget the antenna matching transformer. If those all check out look for things like trees pr mountains that might interrupt the signal. There isn't really much that will keep it from working.

Thank you for getting back to me. I will double check that the two sides are electrically separate but I am pretty sure nothing connects them but the transformer. Is there a minimum distance the bolts should be apart between sides? Also I know my bolts are a little on the long side as compared to the ones in the pictures of your antenna. My bolts are just standard bolts from the hardware store, did you use special bolts? Thanks again for all your help.

rimar20002 months ago

Very good design: nice, easy, cheap and efficient. This week I will make one of these.

rbodell (author)  rimar20002 months ago

Great, let us know how it comes out.

rimar2000 rbodell2 months ago

Well, after a few days doing other things, today I finished and installed it. It works perfect for UHF, but for VHF is poor. I wonder if the adapter 300 to 75 Ohms is really necessary.

The hardest part of all was placing it on the ridge of the house, because put in place the reins to stand it upright was not easy, I broke four colonial tiles, which are not cheap nor easy to get.

At end, I am very satisfied with the result, thanks for the idea. I regret not having taken any photo, is that I worked hurry because here is winter and the afternoon is short.

dgwatson55 months ago

Check out my variation on the present design. They both work well from inside the house. Outside function should be great.

Dontenna 1.0 (1).jpgDontenna 1.0 (2).jpgDontenna 2.0.jpg
rbodell (author)  dgwatson55 months ago

Great, thanks. If it works out do an instructible and put a link to it here. You might experiment with the spacing between the two rings. That could affect the operation some.

clive singh5 months ago

Hi there,

I recently came across your homemade omni directional VHF antenna and I decided to make one. I live in Guyana and approximately 30-40 miles from the source of transmission. The antenna is picking up the signals at a guesstimate of 75 % of full clarity.
I tried adding a amplifier/ booster but somehow it just made the signal strength weaker and had to take it off. what addition/ or adjustment can I make to get a stronger signal? The current diameter of the copper circle is 28''. Does the diameter size pose a problem?

Awaiting your response. Thank you. I appreciate all the information that I have gathered from the website.

rbodell (author)  clive singh5 months ago

Try to get the diameter to 26 inches.

get it as high as possible. Trees and hills in the line of sight will weaken the signal.

Also make sure the two halves of the copper are electrically disconnected. You don't want them to tough.

omnitenna made it!6 months ago

Thank you rbodell for providing the instruction to build this great omnidirectional TV antenna. I also built it with excellent result, see picture below. Please take a look at my patent pending Circular Folded Crossed Dipole (CFCD) omni directional TV antenna "Omni UVOX" at http://www.omnitenna.com

Halo VU antenna plugged 010.jpg
rbodell (author)  omnitenna6 months ago

Glad it worked out for you. I like the one you also built. Very nice design.

omnitenna rbodell6 months ago

Thanks, this commercial omni antenna design shown on the above image is the epitome of 2 prototypes I also built for testing, I'm very proud of it.

WiFi20006 months ago

This looks amazing; I appreciate the pics and instructions. However, I'm not wanting an antenna outside. Has anyone tried this model in an attic? Would any adjustments need to me made (besides omitting the 20' pole, of course)?

All my nearby HD broadcasters are within 11 miles (most are within 5), but I need an omni-directional antenna since ONE of them is nearly 110 degrees away from the cluster where all the other ones are.

rbodell (author)  WiFi20006 months ago

Being that close you could probably put it anywhere. In the attic would be out of the way. You shouldn't have to make any adjustments. Metal objects close by might affect it.

macabrebaby10 months ago
I noticed you used a 75ohm coaxial cable to connect to the matching transformer. Is this part of the design or would a 300 ohm ribbon work better instead?
rbodell (author)  macabrebaby10 months ago
Interesting question, thanks for asking. I see no reason it shouldn't work as long as you have an older television where the antenna connection has screws you can put the other end under. If not you will need the matching transformer on the television end of the 300 ohm cable to connect to the more modern coax connection.

As for it working better, I Don't THINK so.
The ground around the outside of the 75 ohm cable shields it from other signals where the 300 ohm wire won't be protected from spurious signals of different frequencies such as engine spark plugs florescent lights and transformers.

With the ribbon wire you mentioned, the spacing is determined by the frequency. I don't even know if the ribbon wire does reject any outside signals from other tv frequencies. AS FAR AS I KNOW the spacing only keeps the signal from interacting between television frequencies and coax protects it from all frequencies. Would somebody correct me if I am wrong.

In the end it will probably be harder to find the 300 ohm wire and I seriously doubt the price will be worth the hassle.

If you do give it a try, please comment back and let me know the results of your experiment.
It's a perfect tv antenna. Its omnidirectional design is just right where we live considering the source of the signals from different tv stations at different strengths. Now, I can pick em all up like they come from just one direction only. But my only problem was that the loop offers a strong invitation to birds to alight on the tubes. One medium sized bird did alight one day and broke my PVC ... I redesigned the loop to face the wind instead ... the signal is still the same. . . but the birds are gone. Thanks a load.
Actually, coax and twinlead prettymuch equally reject noise. The reason twinlead rejects it is because it's a balanced pair - and the noise is equal on both leads - it gets canceled out in the input transformer, as long as the noise signal is equal on both leads.
The disadvantage with twinlead is that it shouldn't touch metal, which can change the impedance on the cable. That's why the standoff insulators are important when using twinlead.
rbodell (author)  deirdrehbrt9 months ago
Thanks for that.
dcannaday2 years ago
Could you use a 26" rim to bend your copper tubing around?
rbodell (author)  dcannaday8 months ago
Yes, that is what I used to use till I found that it didn't have to be that exact. It looks better but approximate works too. In fact the first one O made was just cutting 26 inch rim in half, but it eventually got rusty so I switched to copper.
peapod739 months ago
Thank you for posting! You mention using a 300 ohm matching transformer. Can I just buy a 75 ohm balun from the store? If not, where can I get the transformer? Do you need to use an amplifier with this?
rbodell (author)  peapod739 months ago
The transformer is found in any store that sells tv accessories. Most are rated 75 to 300 ohm. I have never seen just a 75 ohm transformer. hey are commonly used to connect the cable to the old style connector on the back of the older tvs with screw connections instead of cable connections. I did a search on google shopping and found thios results. These are all the same thing 75-300. If these are what you are looking at look closely at the package, it probably says 75-300 ohm. I can't imagine just a straight 75 ohm. If it ois in the TV section, it will work

https://www.google.com/search?newwindow=1&hl=en&tbm=shop&sclient=psy-ab&q=75+ohm+matching+transformer&oq=75+ohm+matching+transformer&gs_l=serp.3...269274.269508.1.271068.2.2.0.0.0.1.296.436.0j1j1.2.0.ernk_timecombined...0...1.1.32.serp..2.0.0.bolY0eZ3zWA&psj=1
peapod73 rbodell9 months ago
Thanks! I think I get it now: 300 is the antenna side and 75 is the coax side. (I thought they were two different kinds before.) If moving my current antenna to the attic doesn't get me the CW, this looks like it will!
rbodell (author)  peapod739 months ago
The higher you can get it the better it works. Mine is 20 feet. Don't go overboard though. You can get great roof mounts. Trees make a good place to mount an antenna. Just don't get yourself killed before you see how good this works LOL
rbodell (author)  peapod739 months ago
OOPS I forgot, No you don't need an amplifier. If you have the old style TV you will need the converter box. this converts the new frequency to the frequency recognized by the old style TV.

If you are not sure what tv you have you will need to either get a converter or newer tv. Check prices for both. I got a real nice small flat screen at Walmart for about 125 dollars. It worked so well I bought two more, One for the xbox so I could watch TV and play the xbox at the same time LOL. Walmart has flat screen tvs for $99 up

http://www.walmart.com/search/search-ng.do?Find=Find&_refineresult=true&ic=16_0&search_constraint=0&search_query=flat+screen+tv&search_sort=4&_mm=
29tom291 year ago
Built this quickly and it works very well VHF. However doesn't work for digital. freqs required are 562MHz,578MHz, and 594MHz. Any suggestions what to try? smaller diameter?
29tom29 29tom2911 months ago
Got your original to work - problem was faulty uhf tuner box. Redesigned your ant. specifically for UHF frequencies ( 578MHz) - worked well.. Diameter = 16.9cm
rbodell (author)  29tom2911 months ago
Great, would you put up an instructable for it and give a link here so people coming here can see it.
rbodell (author)  29tom2911 months ago
OK I found out your problem. This is not a converter it is an antenna. You still need the converter unless you have a newer television that receives those frequencies.
rbodell (author)  29tom291 year ago
Unless you have some trees in the way of the stations or they are out of range or there is a BIG change in the diameter from the plans you should not have a problem.

Maybe check to see that the two halves of the antenna are not electrically connected causing a short. It is pretty foolproof. . I have had people just guess at the diameter because they didn't have anything to measure with and they had good results.
1-40 of 79Next »