maco 5-element to stacked 5 or 8-element maco

[Shockwave]

If you double the length of the boom and get all the elements perfectly tuned, you'll get a barely noticeable 1/2 S-unit (3db) increase. Long before you notice the increase in gain, you see the effects of a tighter pattern. If you don't know the exact part of a state the person you're' talking to is in, have maps on the wall with compass bearings marked out from your location and know how to work a good rotor well, the larger antenna can be a setback for some.

Case in point, here in Connecticut magnetic north is about 14 degrees off from true north. Just about everyone calibrates their rotor box and beam with a compass. If you do that here, you're off 14 degrees and with an 8 element beam, that's a make or break situation in DX.

One last point. Rotors that flip your boom from vertical to horizontal are not a good option on smaller HF antennas. I wouldn't even try it on anything less than 5 or 6 elements. The driven element would be close enough to the supporting tower and mast to cause a large change in impedance as that element gets closer or further from the vertical tower or mast. Before you invest, just try loosening the boom bracket enough to roll it 90 degrees and see it the VSWR is still acceptable.

 

[arc1]

In my opinion, if you're considering stacking with hf, just go all out, otherwise it's not worth it. It does also depend on your situation and requirements. For instance, you may stack at certain spacing and loose your rear rejection. All of a sudden that street light is affecting your receive in a critical direction. You need to do your research on the half power beam width and calculate the appropriate spacing. You have to realise that achieving an extra 3db is not realistic, let's say you're chasing 2.5. Now you have figured out the spacing, you realise you're going to have to get the top beam up real high (one stacked above the other) because otherwise the bottom beam will be too close to the ground, when ideally you want both beams to be in near identical surroundings. Then you have to pay attention to the feedline, phasing harness/power divider. Then there's the bandwidth associated with this because it is cut to the design frequency. See how the single larger beam is now looking more attractive? Go all out or not at all, and I mean two big beams as well.

 

[arc1]

I would never mount a beam for 11 meters Horizontal since it kills all of your local mobile & most base station signals because of the 20 plus db of attenuation it has from a vertical signal.You can work plenty of skip on a vertical beam & still hear the locals as well.Skip signals change polarity when bouncing around so I don't see the advantage of being Horizontal when the band is pretty much Dead most days for anything other than locals?

SIX-SHOOTER[/QUOTED
Most of what you said is valid, but why deny yourself of a horizontal antenna with a potentially low noise floor. There is no comparison when it comes to DX.

 

[W4KVW]

The whole purpose of horizontal polarity is to accomplish:
1- Reduction of vertical signals that interfere with communication
2- Reduction of noise, most man made noise is vertically polarized
3- Increase the far field lobe of the transmitted signal
As far as number of elements & gain go after 4 elements the amount of gain
diminishes a lot .75 for the fifth- . .5 for the sixth- .25 for the seventh.
The spacing of the reflector and the driven element affect gain more than number of
elements, the length of the boom plays an important role in a yagi.
As far as band width the diameter of the elements determine that, thicker is better.
You guys that have been in the game a while remember the Wilson Long John?
It was the biggest bad ass 11 meter antenna you could have back in the 70's
The length of the boom is what gave it tremendous gain, not the number of elements.

I remember the Wilson Super Laser 500 on the 40 ft boom.A local friend had one on a 40 ft tower & it was a MONSTER in the air & on the air.Having bot Vertical & Horizontal elements made it a Perfect antenna for local & distance communications when people actually had conversations on the CB & communicated.

SIX-SHOOTER

 

[552fl]

Yes definitely will be getting a metal tube box
Five more years before I retire.. gonna be a seven or eight element maco beam.. right now.looking at either a ghost Rider or wizardbuilt when I retire I live way out in the country .. born and raised Florida boy
. But it seems like the whole country is wanting to move to Florida for some reason.. till it gets hot and then they haul ass back up north
.

 

[W4KVW]

Yes definitely will be getting a metal tube box
Five more years before I retire.. gonna be a seven or eight element maco beam.. right now.looking at either a ghost Rider or wizardbuilt when I retire I live way out in the country .. born and raised Florida boy
. But it seems like the whole country is wanting to move to Florida for some reason.. till it gets hot and then they haul ass back up north
.

I would not have an issue with them moving here to Florida but only if they would bring some Snow & Cold Weather with them when they come.

SIX-SHOOTER

 

[lrz50]

All the snow birds are heading out of Arizona all so. They start there journey home just before or after Easter. The stores and roads aren't as crowded when they get out. Getting are first 90's'of the year next week. Next stop 110

 

[Henry HPSD]

A tigther pattern which allows you to illuminate the unwanted is always welcomed. for RXing.
That....together with the additional gain could be an improvement. But..... only if you are really into "DX"... and hearing them. Primairy focus on height....you probarly cant change the terrain on which the antenna stands hihi.... But if you can....slooping ground about 10..30 degree downwards upto about 10...20 wavelengths from the antenna would be nice.
It is wise to invest in heigth rather than boomlenght (up to about 60 feet high) then the number "boomlength" becomes of interest. If that is from a single boom or dual is open for discussion.
And the mechanical aspect....it is rather easy to put up a 6..7el about 60 feet of the ground but anything beyond becomes a serious task....not only to get it "there" but to "keep" it there aswell.

So overall....if you can put any beam up as high as possible.... If you are done with "heigth"....get as much boom up as you can.

73 Henry

 

[M0GVZ]

One advantage to stacking them, one at half wavelength and one at one wavelength high for example is the ability to switch between them to give you better contacts at varying distances. For example the one at a wavelength high is going to be worse for nearer contacts than the one at half a wavelength high

If we look at the chart below for elevation angles and arrival angles above 18 degrees the half wavelength high starts to win, becoming at 30 degrees (close signals within a few hundreds to a thousand miles) nearly 20dB better. During contesting I've been in the position of having to lower my antenna because at 60ft high I couldn't hear let alone work anything under 2500 miles away.

 

[Shockwave]

One advantage to stacking them, one at half wavelength and one at one wavelength high for example is the ability to switch between them to give you better contacts at varying distances. For example the one at a wavelength high is going to be worse for nearer contacts than the one at half a wavelength high

If we look at the chart below for elevation angles and arrival angles above 18 degrees the half wavelength high starts to win, becoming at 30 degrees (close signals within a few hundreds to a thousand miles) nearly 20dB better. During contesting I've been in the position of having to lower my antenna because at 60ft high I couldn't hear let alone work anything under 2500 miles away.

It's great to see that in a visual reference. I once made the mistake of raising a Shooting Star to 72 feet from about 40 feet. It destroyed my ability to work southern skip from CT on the horizontal side. Going from 1 wavelength above ground to 2, will make your signal 100 times WEAKER at the 15 degree take off angle! An angle that is useful for closer DX work. Notice the chart shows there is more than a 20db difference in signal at 15 degrees. Adjusting the height of your beam to reach your targeted area can be far more useful than adding power or more elements.

 

[Mustang 131]

Yes definitely will be getting a metal tube box
Five more years before I retire.. gonna be a seven or eight element maco beam.. right now.looking at either a ghost Rider or wizardbuilt when I retire I live way out in the country .. born and raised Florida boy
. But it seems like the whole country is wanting to move to Florida for some reason.. till it gets hot and then they haul ass back up north
.

$750 to register just my Tahoe this year...do I need to say any more.

 

[Mustang 131]

Hello All: A good friend of mine insists on having a 7 element beam antenna. I tried to talk him out of it by using a 5 element yagi beam Antenna that works for just great.
I talk to the weak stations in the South Pacific Islands, while rejecting the big boys out of the southern states with all their steam.

The 7 element yagi beam antenna will half to have a more BIG EXPENISEREER Rotor and Tower. The gain is only a few dB in gain and in rejection at the expense way more money. But your allowed to be a nut ball on this stuff if you have the money.

Experience has shown that starting out small and working your way up to the big stuff is the only way to go. I then suggested a crank up/down tower that can be tilted down as this is way more money and saves going to the emergence ward. Buy a already in production 7 element yagi beam with a Balun and Hairpin Matching, what is called direct feed to the driven element. SEE:

https://www.m2inc.com/FG11M7

For me to build and have the materials shipped to me to build, test, and ship back to the south, costs way more than the $1500.oo plus shipping these guys want for their 7 element yagi beam antenna.

They also sell a 5 element yagi beam antenna, for a little cheaper. Again NOT using a single Gamma Match! But using the Balun and Hairpin matching system.

You can call the factory and get the poop on the stacking distances and I am sure they can suggest a Rotor and Tower. $$$$

Good luck.

Jay in the Great Mojave Desert

That's s pretty damm good looking antenna...price ain't bad either. But I'ld rather have you build me one in a heartbeat.

 

[552fl]

Come on down we need y'all's money....one of the guys on the 28th good time gang Channel wants to buy my 5 Element said he would give me 225 for it . I said that's fine I only had it up 6 months going to get the 7- element maco . 550 total that includeshipping to florida from r&l Electronics
. So it would only be 335 not bad that's what I paid for the 5 when I bought it