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Military Firearm Restoration Corner

Outdoor Hdtv Antenna


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If you are in a big city, you may be able to get by with just a small cheap near your TV. Otherwise get a larger one with an amplifier. And the little fen dollar ones are better than nothing, but spend more and get a better one. One with a motor to turn the antenna is better yet. With antennas, in general, bigger is better.

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So, Karl, 7 years as a Radio Electronics Officer in the US Merchant Marine didn't go to waste? :D

 

We dumped satellite TV years ago. We watch whatever we can get over the air for free or a movie downloaded or amazon prime'ed.

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One of my renters uses a interior FM radio antenna. Nearly all broadcast TV in Phoenix comes off a high mountain in the southern part of the city. Couldn't count all the coax I saw running between houses and apartments while delivering mail. One guy was caught and arrested for tapping into underground TV cable and running extension cords from a streetlight's inspection plate into his circuit breaker box.

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Loaded question and many variables....

 

Indoor or outdoor?

UHF-only or some VHF too? (ch2-13 VHF, 14+ UHF; real, not virtual)

Distance to sources?

 

Look here for some cool designs:

http://clients.teksavvy.com/~nickm/gh_u/gh0_10u45.html

 

For UHF-only, the Gray-Hooverman is hard to beat. Even the simple GHO as linked above (elements only) has a dbi over 8. A roll of 1/8 copper wire would do on a thin sheet of plywood. Elements-only has the advantage of 180 degrees.

 

Fun project.

 

Just do a search for Gray Hooverman for design ideas. Indoor doesn't need fancy frames.

 

Have you looked at tvfool.com to get an idea of directions?

 

 

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Another interesting link:

http://www.hdtvexpert.com/tag/walltenna/

 

For indoor and local, that old "rabbit-ears" bowtie works fairly-well. Many folks have them tucked-away.

 

A friend had a couple. Took one and added a $1.28 "matching transformer" from Menards. An example of what I'm talking about here:

 

https://www.amazon.com/RCA-VH54R-Matching-Transformer-VH54R/dp/B00005T3EY/ref=sr_1_1?ie=UTF8&qid=1499918393&sr=8-1&keywords=matching+transformer

 

drilled a 1/4" hole in a scrap 2X4 and bough 1/4" wooden dowel stock. I think I have about $3 in a fully-functional indoor UHF antenna.

 

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It was an GE Pro Yagi. And I got it aimed at Kansas City. Think of moving it more to the west just an hair to see if rrwo other cgenbal clear up. Range say up to 70 miles and it was free so I can not complain not one bite. Used my Wal-Mart saving catcher to pay for it.

 

Rob

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It was an GE Pro Yagi. And I got it aimed at Kansas City. Think of moving it more to the west just an hair to see if rrwo other cgenbal clear up. Range say up to 70 miles and it was free so I can not complain not one bite. Used my Wal-Mart saving catcher to pay for it. Rob

Yagi antennas are very directional with a narrow beam width. Great for sources in a single direction.

 

I have two banks of antennas 180 degrees apart. I'll need something different.

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Two Yagis connected to the same length coax with a splitter would probably work for you, GN. Point one Yagi at each of your source antenna sets. That would give you some gain. If they are not that far away, a simple dipole has two main nodes 180 degrees apart, 90 degrees from the axis. No gain, but it would pull in from both sides.

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Two Yagis connected to the same length coax with a splitter would probably work for you, GN. Point one Yagi at each of your source antenna sets. That would give you some gain. If they are not that far away, a simple dipole has two main nodes 180 degrees apart, 90 degrees from the axis. No gain, but it would pull in from both sides.

I've had it beat in my head that you can't do that; you'd need a rectifier for that. I could do it with an A/B switchbox, though.

 

You can combine antennas on the same cable with a splitter, provided the antennas don't overlap on frequencies; a VHF-only and a UHF-only would be fine together.

 

I'm in the process of building a GH0, element-only antenna. With no reflectors, I can get 180 degrees. It'll be a larger version of the flat wall antennas that are in vogue right now.

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Well, dunno who is beating your head, but they know squat about antennas. There are plenty of examples of two antennas on one coax on the same frequency. Google up "phased array."


BTW, I did this stuff for a living once. People paid me very good money for it. Besides 40 years of amateur experience.

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Well, dunno who is beating your head, but they know squat about antennas. There are plenty of examples of two antennas on one coax on the same frequency. Google up "phased array."

 

BTW, I did this stuff for a living once. People paid me very good money for it. Besides 40 years of amateur experience.

I appreciate your feedback, and I'll look into it. This is generally what I've found:

 

https://forum.tvfool.com/showthread.php?t=1177

 

http://www.avsforum.com/forum/25-hdtv-technical/939550-can-i-combine-antennas.html

 

Again, I'm partway done with my 180 degree project, and if everything works right I'll just need one antenna. My locale has no surviving VHF (OK, the one VHF PBS channel has a UHF counterpart), so I only need to worry about UHF.

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A simple 180 degree yagi design would be to take 2 regular Yagis, cut the reflector(s) off of one and cut the support beam at the driven element on the other, and put the directors behind the driven element of the first. So you would have: Directors, driven element, directors. Set it up so that the distance between the driven element and first director is exactly the same both ways. Someone did the math for you on the first one, so use that distance. That should do 180 degrees for you and one feed point. Note that is using Yagis, not Log Periodic antennas. Yagi's have one feed element. Log periodic are all fed. Yagi's are designed to work best on one frequency. Log periodic work about the same on all frequencies within their design spec.

 

Still, the easy way would be to just put two antennas up and as along as your coax is exactly the same length up to the splitter, you should be fine.

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