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I decided to try a little different testing with non pre-amped antennas. Sometime last year I purchased 2 Winegard HD 8800 brand new in the box. I was surprised I could find them now I kind of know why. When I first saw them on the HD Primer website, I saw the charts and thought it would be the perfect antenna for the repack. Later I found out there must have been some errors in the antenna modeling because this is a substandard antenna. Winegard has since dropped a design. It has floppy active elements that barely click into their plastic brackets when unfolded. A simple landing from a bird makes will fold down an element. The rest of the antenna seems to be okay. I figured before I sell them I will use them in a test.

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I had them stacked aimed at Milwaukee with a combiner in reverse, performance was okay but that's not what this test is about. I decided to rotate the top one and very carefully aim at Chicago. I found that it did seem to matter even though a piece have a reputation for a wide beam width I patiently and each 8800 at each DMA.

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With that out of the way, I was ready to do some testing first I used a Holland splitter in reverse. From the splitter I used a Kitz Technologies KT-200 to about 50 feet of RG-6 Quad shield. :unsure:

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I did several sweeps and the results were very consistent. It is exactly what I expected with Chicago stations overpowering the Milwaukee stations. Believe or not there's no co channel interference, the only thing I have going for me

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As expected, The Milwaukee signals were much weaker due to the greater distance (49 Miles Vs. 39 Miles). Also, I suspect some of the Chicago signal "leak through" the Milwaukee antenna and Vice Versa. This is a complete phase mismatch and I can prove it later.

I immediately hooked the SmartKom:

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Although SmartKom cannot make a weak station come in (that is up to the antenna) it can certainly block unwanted interference from unwanted stations on the desired antenna and that is where the signal quality gets improved.

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OK, Here is proof of just how bad things can get. Because SmartKom chioose stations by strength, the problem with the antennas allowing signals to "slip through" even though aimed 180 Degrees opposite, Domination of input # 1 is evident behind the adjustment window. Here, I am adjusting input 2 for MKE:

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First, unwanted Channels had to be deleted from input 1. RF8, 30. Easy to do.

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Learning plan (H30 scan) with Holland Splitter:

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Learning plan with SmartKom:

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Multiple input RF switch for TV antenna testing

I had 5 TV antennas (now 4) and I searched hard and I tried a few of the old consumer ones like the Radio Shack RF selector in your photo and they were all useless because they lack sufficient shielding/isolation (and, probably termination) so the adjacent inputs bleed into the others. The ham radio transmitter selectors may be better but they only have at most 3 inputs and they have the big, old UHF connectors and they are also relatively expensive. I wound up putting F connector push-on adapters so it’s quicker to switch cables.
 
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