Stacking, Ganging, Combining TV Antennas

[roger1818]

In theory two stacked 4400's should have the same gain as an 8800. In practice it all depends on how much loss there is in your combiner as compared to the loss in the 8800's combiner, so it could be better (unlikely) or worse (likely).

[roger1818]

Originally Posted by balm

So I'll assume for stacking 2 4400's vertically, they should be one right on top of the other (no separation)

I would space them so that all of the elements are equally spaced.

For horizontal stacking, im not sure the separation...

I would start with the same spacing as the 8800. You can go wider if you want to change the position of the side lobes, but I wouldn't go narrower.

[be236]

Assuming that two HD-4400s and one HD-8800 had about the same gain, then it seems "cheaper" to just buy one HD-8800, eh?

As for vertical spacing of two HD-8800s or two HD-4400s, I dont know what you mean by "elements equally spaced." I mean all you can do is move one on top of the other on the same pole/mast and aim it at the exact same direction.. what other control can you do??

[roger1818]

You can increase or decrease the distance between the antennas (by raising or lowering one of the two antennas). Optimally you want them so the top element on the bottom antenna is the same distance from the bottom element on the top antenna as all the elements within the same antenna are.

Rough text diagram:

Like this:

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not:

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nor:

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[balm]

OK, horizontal separation on the PR8800 is 23 inches, according to Ken Nist

I was also wondering what it is on the newer HD8800...if anyone has one

thanks

[be236]

Ah... thanks for the drawing... I can see it better now... now I understand.. basically make all the elements equi-distance to each other between the two antennas... Got it!

[be236]

I can't believe no one here as an HD-8800 yet? heh...

Well, I plan to buy one soon, from Amazon for roughly $50.

[roger1818]

AFAIK, The HD-8800 is exactly the same as the PR-8800. The name was only changed for marketing purposes.

[be236]

On another note. I currently have the older CM 4221... would it be feasible to buy a CM 4221HD (can't get older model these days) and vertical stack them, though they are slightly different design?

[balm]

roger1818, thank you, I was not sure about that.

[balm]

be236,

here's another thought on yours, I was thinking of combining 2 identical models of 4221. Iwas thinking it might be as good or better than a 4228, especially if the 4228HD has to be hacked anyway, AND it would be cheaper...just thinking...

(I know the 4228 vs 2x 4221 comparison was discussed already)

[someguy23475]

I'm not planning on adjusting my current antenna (the CM-3671) anytime soon, but reading these posts make me wonder something.

In my situation, I have a wide range of UHF signals, all VHF-HI signals except for 12 which is there but too weak to lock currently, and a weak mostly unlockable signal on VHF 5. I was thinking that if I had stacked antennas for UHF, VHF-HI, and an antenna specifically for channel 5, would that increase my reception range for fringe stations enough to be worth it? I do have a preamp currently and would continue to use one with this proposed setup.

In case you are wondering about distances: the channel 5 is roughly 49 miles away with a slight null in my direction, the channel 12 is about 75 miles away, and the far range UHF stations are about 60-65 miles from me.

[Jase88]

The CM-3671 is a decent antenna. However, I'm of the opinion that most combo antennas are a compromise.

Looking at HDTV Primer's comparison of common commercially available antennas, the CM-3671 actually does very well on VHF. You can't beat it with most other VHF-only antenna for channel 12.

On the UHF side, there is some room for improvement over the CM-3671 with competing antennas. In particular, the XG-91 by Antennas Direct.

While others may disagree with me, I've never been a fan of stacking and combining same-band antennas to increase signal for weak stations. The realized gain--if present--is often marginal at best.

I would investigate other possibilities, such as increasing antenna height with a tower. Greater cost and hassle, yes. But the results may well be far better than you could obtain with stacking or combining.

[someguy23475]

I've actually raised the antenna from 20 to 40 feet above ground, and it does make a slight difference on the weak stations.

My next system, whenever that will be, I will try getting an antenna dedicated to UHF and see what happens. Only problem I may have with the XG-91 by Antennas Direct is that the author advises not to use this under 25 miles, and my locals are in that range.

[hoopitup2000]

Originally Posted by someguy23475

. . . . Only problem I may have with the XG-91 by Antennas Direct is that the author advises not to use this under 25 miles, and my locals are in that range.

No need to worry. I have installed three 91Xg's in mega strong signal area's & they are all stellar performers with both strong & weaker signals.

As far as overload is concerned, it's rare that you can ever have too much antenna. Over amplification causes most overload issues.