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Discussion Starter #1 (Edited)
Best Home Brew, Do It Yourself OTA Antennas:

Very High Performance, may be complex to build, may require some shop skills:

Good Performance, less complex to build, suitable for hobbyists and inexperienced:

Less powerful but convenient, easy to build:



Antenna Research & Development:
For those of you wanting to take part in leading edge technical design, computer modeling, building, research and development of antennas at our site:


Tips & Tricks For Antenna Construction:


What NOT To Build:
Before wasting your time or ours on an antenna that you saw in a video or found on a website please read these threads:
 

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Comparitive Performance Chart - Large DIY UHF Antennas

Single FF6 is only 1 dB lower Gain than subject G-H and several Antennas that have higher Gain are found in the Gain Comparison Chart below....you'll have to decide yourself whether they are "Easier" to build, such as:

Vertically Stacked M4 (9.5x9) with Double Angled Reflectors (BTW: mclapp sells prefab Bowtie Assemblies).

And for significantly HIGHER Gain, Vertically Stacked FF4 or FF6, where I think it's pretty simple to cut out a piece of "fencing" material to size and bend it a couple times for the Screen Grid Reflector (plus I suggest a 45-deg forward bend in outer 2-in to improve rigidity):
Stacked Antennas - ImageEvent
Multi-Bay Bowtie Antennas - ImageEvent

KISS Quasi-Parabolic is also pretty simple, using four large square FLAT Panels (could be "fencing" material) and use either the modeled 8-El LPDA....or perhaps a repurposed 7-El Silver Sensor LPDA (aka Terk HDTVi)....or several other alternative Feed Antennas I analyzed for the 10-ft Parabolic Dish [hmmm, they're described in forum posts but I haven't yet uploaded to my website]:
Quasi-Parabolic Antennas - ImageEvent

Like all of these HUGE Antennas (incl. subject G-H), the hardest part is constructing a SUPPORT FRAME that is strong enough to keep it from flying away in a strong wind....or finding a big enough Attic to put it in.....in which case the Horizontally Stacked alternatives may be better suited....

LATEST HIGH GAIN COMPARISON CHART:
[2xFF6 are In-Progress Optimization Results and may improve a few tenths of a dB in next several days]

 

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Discussion Starter #3
Future-Proofing for the UHF Channel Repack

The present channel/frequency/wavelength allotment for UHF TV broadcasting is shown in Post #18 of the OTA FAQ. Simply put, today's UHF TV band consists of channels 14 through 51 (470MHz through 698MHz). By looking up the frequencies for your desired channels you can check on holl_ands chart in Post #2 on how each of those great antennas perform.

Having said that, in the near future it is likely that a UHF channel repack will occur. This means that the UHF TV band would be condensed to a smaller range of channels, and not necessarily starting at channel 14. At least we know that the repacked band will be within today's existing UHF band, so we can thankfully still make use of the great performance info used today.

As holl_ands has reminded me, there is still the likelihood of today's VHF-HI channels remaining in the new mix. He mentions that VHF-LO is also a possibility, although there is still talk in Washington, DC about expanding the FM Radio band into the VHF-LO TV band so there doesn't seem to be any clarity so far on using some or all of VHF-LO as part of a repack.

So, if your chosen DIY antenna has suitable performance for your needs across the entire UHF band you are already good-to-go for the long term. :) On the other hand, if you require performance for an exact set of channels in your area for an antenna that must operate over the long term without change, please keep checking in on the latest news in the following thread to see what decisions the authorities in Canada and the USA may have worked out: Here comes the UHF Channel "Repack" for OTA
 
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