New antenna from Sirio Gain-Master

[bob85]

007, i agree with dave,
i was one of the first people to defend the gainmaster when people said its just a dipole in a tube.
theres more than one way to build the gainmaster style antenna but i don't see the guys stuck on building 5/8wave groundplanes doing it without some help from somebody with a much sharper pencil,
sadly the only builder i have seen out there with antenna knowhow ( eddie wolf ) stopped building cb antennas a while back,

so far i have only seen the gm with my own eyes and ears up against the top-one mounted much lower, next up gm vs imax with radials (a fair fight) then maybe gm vs i10k and gm vs NAPCO

 

[Oggy]

Big Buck antennas

i may have missed it marconi . this thread has taken a life of its own and i haven't read every single post in this thread . if he did that with them on the same mast/feedpoint/location as the predator and it beat the 500 that is indeed quite a feather in the GMs' hat !!!

im thinking the big buck american antenna is referring to the i10k and mr. coily antennas .

Yes Booty Monster indeed it was these two I was thinking about. Before it's pointed out to me I agree the i10K and Mr Coily are superb built antennas .With power ratings second to none. I still would love to try either and I understand real quality costs..........I am a Welder /QA man in my day job and I realy follow the build quality of these antennas for sure and good of these guys to cater for this side of the market, The Gain Master (for the priced charge) could never compete with that aspect ,but around a year ago I was told ,no way I would find a better "Peforming Antenna" than these......well I do think further tests are needed.......but I still fell the SGM is a winner.....for price per "S" Point for sure.

 

[Oggy]

CB Radio and Bullshit??........your Joking right??

I think a great deal of those cynics really do want it to work as well as claimed,the cynism is more likely due to them wanting to ensure it does before spending money.there is always doubt when a new/but good product comes around.

CB'ers have been bombarded with lies and bullshit for decades,when something appears that defies that bullshit sales logic then naturally their will be doubters Dave.

Ebay and retail rip off merchants have done nothing to increase buyers confidence either, it all adds to make them wary of investing money till they are certain its a good investment.

Hello George, indeed a lot of CBers (unlike the WWRF and CT group I add) believe some of these stupid claims . I know many Hams and CBers and most of the ones I know listen to the facts. The main gripe i've had ,was after my tests (and yes OK a same pole test would of proved more....I agree) was "Muppets" on Youtube trying to disprove my (and others tests for that matter ). One UK guy (a so called Radio Amateur) said my claims were void. Now I ask you, I only did the tests for my own reasons of helping Radio Hobbyists. I have never seen too many CB Radio antenna reviewers using £400 worth of analizer....God most of the CBers around here struggle with the concept of a £5.00 SWARR Meter.........LOL. Look at Solarcons claims for their A99 @ 9.9DB........we all know this is as true as the tooth fairy!!. But Sirio are a very respected antenna buider and making Ham antennas too ,we won't be conned very easily. I never doubted their claims ,as I find them truthful and they invested $1 million USD in a shielded Anechoic test chamber for a start. I will keep reading the Stateside and Euro findings........but with a little chuckle. As for the Cynics on Youtube ,I don't normally say "I Told You So!!"......BUT!!!!.......i think your :bdh::bdh: now!!!

 

[Marconi]

I'll have to disagree with that, check out this link;

"...My dozen or so receivers (Drake R4C's, IC-751A's, Yaesu FT1000D, Collins 75S and KWM-2, etc) all range from about 1 or less dB per S unit at S1, to maybe 3 or 5dB per S unit near S-9."

Scott, I'm no technician, so I can't be sure how mine or any other CB Sunit meter reads or at what value. From what I've heard, and for sure that could be wrong, the typical CB meter is said to do about 3 to 6 db per Sunits in a somewhat non-linear way. That is the range I was referring to in my post to BM about your using db's to report instead of Sunits. I didn't consider a db to be 1< per Sunit for these reasons.

I think I talked to you about your reporting in dbs some time back, but I can't recall exactly how it was explained...how & what was done reporting in dbs rather than Sunits. I have a vague recollection that maybe you used an outboard db meter with a large face that was marked up in dbs, but it may have been someone else. Regardless if my recollection is right or wrong, could this make a difference in how we understood your report?

My radios are noted with Sunits below S9 and db's above. I was not aware that you were using the rigs noted in your post instead of a CB or something similar with Sunits. If your radios respond with 1 db or less per Sunit, then my use of the word "insignificant" was wrong. If this is so, then your reports shows even more difference in favor of the GM than I originally though. That makes your comparison of your Imax and P500 vs. your GM to indicate much more difference than my report @ .80 Sunits or Bobs @ 1.5 Sunits difference.

In the same post I commented that your reports might show about what we might expect...with the GM vs. 5/8 wave about equal. But with this information about your receiver showing 1:1< db per Sunit then the GM is much stronger vs the Imax or the P500 on the same mount. My comparisons or Bobs use Top Ones...where the 4' radiator height is at a real disavantage vs. the 5/8 wave. I'll re-think all this, but IMO our reports don't seem to be similar at all as you suggested. That is not withstanding all the possible differences in the ground affects under the antennas, locations, coax, and conditions.

Bob, Oggy, and a couple of others showed a bit more difference than I did, @ .80 Sunits vs their 1-2 Sunits. Plus some of us were using antennas noted to have less gain than a 5/8 wave and were much shorter and lower in cases.

Now considering this new information about your report...we didn't experience near as much difference as you did, and you were using the Imax and your .64 P500. I don't get that, unless your GM is far more effective than I imagined, and if that is so I wonder why my report with an antenna with less gain and a physically shorter antenna didn't show more difference in favor for the GM?

I'm through preaching. I finished my third report with my antennas center to center, with the GM at 49' feet and the TO at 44' feet. The results were not much different than my previous comparisons @ 55' for the GM. After I finished, I did as you suggested the other day, and removed the TO. I did another report in the margins of Signal Report #3 with the GM by itself. I basically saw NO difference in signals vs with the TO present.

Then I pushed the GM pole all the way out making the tip to 55' feet just like report #1. I'm now seeing about 1/2 an Sunit improvement over the same height when the TO was in play. So, maybe you were right the TO was making a little difference even at 35' feet apart.

I was going to switch the antennas and check for differences due to location and coax, but I've decided to do as most are suggesting, use the same mount and coax, at the same height in further testing. For simplicity sake, I think I'll start with my Imax maybe tomorrow if it doesn't rain.

 

[CDX-007]

I'll have to get my iCOM over to my Buddy's tech bench and inject a signal while watching the meter reading, especially around 10-over-S9 where it was reading during my comparison of the P500 vs SGM.

If my 751a reads like his 730 then I'm only seeing about ½ of that perceived ~5dB gain, which would make better sense.

I even have a new meter I bought directly from iCOM which I'll go ahead and install when I test it, before & after, just to see if the old meter was tiring from ~15 years of movement. - I know I'd be tired if I had a 15-year movement.

 

[Marconi]

hello guys there is a couple things here that don't make much sense to me in testing this antenna.1-having antenna heights tip to tip seems like it kind of defeats the purpose of the longer antenna?2-comparing antennas signals at 10 miles?i would take that with a grain of salt.you should at least be comparing these antenna signals at 50 miles plus,hopefully more.most of my comparisons are 50-100 miles.i have found that when testing antennas locally its much harder to distinguish between them.***

I agree 1342 completely.

I was focusing on equal height at the tips, because I had a very short antenna vs. 5/8 wave I wanted to compare in some fair manner. When I say fair, that is my opinion of fair...I'm not trying to set some standard for installation. If you read these post closely, you will note where I've attempted to raise attention to exactly how important height can be when comparing antennas. I'll say it again, if I can get my little antenna with a 4' radiator even at the tips with your 23' 5/8 wave, I can make as good or better signal than you. I can't be so specific in the distant range, but within reason I can show more signal in the typical range for CB.

In a normal world of a CB operator, height is not that important, and many just ignore the details of explaining what they do when they discuss their comparisons or opinions about the antennas they use. That is fine with me and probably as it should be, so just call me an antenna nut.

IMO, we all agree that setting up a vertical antenna should be a simple matter of putting it on the support of choice and getting it up as high as reasonably possible and still be save and comfortable at the height installed.

Most guys would not be shifting their antennas around like I do...trying to see if or how their responses compare with changes in height, tune, coax, and sometimes even construction or design. It might be said, I'm more interested in what piddlin with my antennas can show me...than listening to the BS my buddies have repeated over and over and over for over 40 years now. I still talk some on my radios some though.

If you look back at my signal reports posted in this thread, you'll see some verification of what you say regarding stations close vs. at a distance in the numbers. So, IMO this GM is likely to prove out to be a real good long haul RX/TX beauty.

It is in those longer contacts that I see the more notable differences in signals. Of course the bunch I hang out with are known to be switching antennas, beams and direction, flippin' on amps, and getting new radios, so those observations I mention are not 100%.

When my old buddies say to me,

"...hey Grampa what have you done now, your signal is much stronger and clearer---and I can understand you much better now."

I tell em' "...it must be the Good Lord making conditions good," and otherwise I don't tell em' nothin' else." I do grin a little, knowing this Gain Master is a marvel that I can't believe, but I could never convince these guys about nothing.

1342, I'm more impressed with the clarity of signals I receive and how quiet this antenna responds when conditions are good and quiet and even when a little noisy...than I am with the actual gain in signals I often see while comparing antennas. If the Gain Master transmits what I hear, and it does, then more better.

That is my opinion.

 

[Marconi]

I'll have to get my iCOM over to my Buddy's tech bench and inject a signal while watching the meter reading, especially around 10-over-S9 where it was reading during my comparison of the P500 vs SGM.

If my 751a reads like his 730 then I'm only seeing about ½ of that perceived ~5dB gain, which would make better sense.

I even have a new meter I bought directly from iCOM which I'll go ahead and install when I test it, before & after, just to see if the old meter was tiring from ~15 years of movement. - I know I'd be tired if I had a 15-year movement.

Well 007, that is not exactly good news for you, but I'm relieved that my GM is more representative of one that is working about typical.

I would expect these three antennas you're comparing to be about the same mounted on the same pole, with the Imax maybe a bit behind just due to the matching required for doing without radials. That said none will be even close with how clear and how quiet this GM is. I think the GM's Band Width is an advantage too, even compared with the Imax.

Here also is what 1342 had to say on the subject of you large differences:

cdx cant wait to hear your results, as marconi stated 1-3 s units between his astroplane sounds about right,however i dont expect to see that kind of difference between your penetrator and imax and sgm.i guess we will have to wait and see.

However, let me add that my signal reports indicate that the AstroPlane is still very competitive with these larger antennas...when I raise it up a little higher at the feed point without even getting the tips equal. Somewhere around about 10' feet higher for the AP it starts to show much better comparative signals with the still much higher radiator.

 

[Marconi]

Final Signal Reports GM vs. AstroPlane

Here are my final comparisons for my new Gain Master vs my Top One at various heights.

I did not test with both antennas mounted with the TO hub and the bottom of the GM at the same height, but I suspect that Bob and others who might compare such signals are correct, the TO would be noticeably lower in signal.

The reports note the relative heights for tips and absolute bottoms for the antennas.

View attachment Gain Master vs. Top One.pdf

Next I plan to compare the GM with and Imax, I-10K, and maybe my Sigma4, all with the same mast, height of mast, coax, and location. I predict my Sigma4 will show the best signals due to its superior height at my location.

 

[CDX-007]

OK Marconi,
I'm looking forward to the I-10K & SigmaIV comparisons!

I hope you can try the SGM & the SigmaIV with their tips at equal height.

And it sounds like the surprisingly competent AstroPlane / Top One would be great for mountain top or other high elevation installations where height isn't an issue, otherwise in at least 70-80% of installations I'd expect it's performance would take a noticeable 2nd place compared to other taller antennas. But it sure is an interesting design.

 

[Marconi]

OK Marconi,
I'm looking forward to the I-10K & SigmaIV comparisons!

I hope you can try the SGM & the SigmaIV with their tips at equal height.

And it sounds like the surprisingly competent AstroPlane / Top One would be great for mountain top or other high elevation installations where height isn't an issue, otherwise in at least 70-80% of installations I'd expect it's performance would take a noticeable 2nd place compared to other taller antennas. But it sure is an interesting design.

Me too 007. I hope I have the energy and the weather doesn't get too bad.

If I did get the GM up to the tip height of my Sigma4, my past experience would tell me I should see the GM show noticeably better signals on increasing the height. IMO with such a case however, we would have to debate where the actual feed point is on the GM, and then based on that consideration, figure out what advantage that might be, and what would we do or expect to see if we raised the GM 7'-9' higher to the tip of the Sigma4. The setup might spread the actual feed point advantage as much as 19' apart to the advantage of the Gain Master. How say you?

I use to think in a "run what you brung" comparison on a 50' foot mast...that it's unfair for the shorter antennas, and it is. But in the real world...put all antennas on the same pole and let the chips fall where they may. In this case, if you don't have a Sigma4/Vector type antenna you might as well stay home.

Now in my comparison work, I may do things differently to try and get an even playing field.

 

[CDX-007]

Me too 007. I hope I have the energy and the weather doesn't get too bad.

If I did get the GM up to the tip height of my Sigma4, my past experience would tell me I should see the GM show noticeably better signals on increasing the height. IMO with such a case however, we would have to debate where the actual feed point is on the GM, and then based on that consideration, figure out what advantage that might be, and what would we do or expect to see if we raised the GM 7'-9' higher to the tip of the Sigma4. The setup might spread the actual feed point advantage as much as 19' apart to the advantage of the Gain Master. How say you?

I don't yet ascribe to your feed point theory simply because it's the entire antenna, not the feed point, that radiates and I believe it's more about pattern than feed point / match design, etc.

I'm going to re-assemble the Saliut and check it's radiation with a field strength meter so I'll be able to buy into the 'lower-section-radiates' theory, until then I'm still of the camp that it's an elevated bottom-fed ½ wave.

Do you know if anyone else has already tried the field strength meter test on the Saliut / LW-150 / SigmaIV / Vector 4K?

I use to think in a "run what you brung" comparison on a 50' foot mast...that it's unfair for the shorter antennas, and it is. But in the real world...put all antennas on the same pole and let the chips fall where they may. In this case, if you don't have a Sigma4/Vector type antenna you might as well stay home.

Now in my comparison work, I may do things differently to try and get an even playing field.

Well, that's what I'm really most interested in, your test of the Vector against the SGM with both at identical mast heights, and as such I believe the Vector will have a height advantage of about 9', in MY opinion, as I'm not yet a 'radiating cone' believer.

- But I'd also love to know how the two designs compare without there being a tip to tip height difference.

 

[Oggy]

Let The Game Commence !!

I don't yet ascribe to your feed point theory simply because it's the entire antenna, not the feed point, that radiates and I believe it's more about pattern than feed point / match design, etc.

I'm going to re-assemble the Saliut and check it's radiation with a field strength meter so I'll be able to buy into the 'lower-section-radiates' theory, until then I'm still of the camp that it's an elevated bottom-fed ½ wave.

Do you know if anyone else has already tried the field strength meter test on the Saliut / LW-150 / SigmaIV / Vector 4K?



Well, that's what I'm really most interested in, your test of the Vector against the SGM with both at identical mast heights, and as such I believe the Vector will have a height advantage of about 9', in MY opinion, as I'm not yet a 'radiating cone' believer.

- But I'd also love to know how the two designs compare without there being a tip to tip height difference.

As The Guy in the Movie Saw says.........."Let The Game Commence!!"

 

[Marconi]

Well Scott, I've consider this idea about the importance of feed point elevations relative to antenna comparisons and my thoughts surely could change with a more convincing idea about the subject.

There is usually a maximum current node around the feed point area of most antennas, with the exception being an end fed at a voltage node similar to the A99, but not necessarily the Imax. I think most will agree that the Vector's feed point is at the gamma, albeit is rather long, so that length might even matter a bit. In any case the Vector feed point is real close to one of its maximum current nodes which happens to be very near the base. The 5/8 wave GP and the 1/4 waves are typically about the same, so that is not an issue.

The Gain Master on the other hand is described to be center fed and the coax exposes the radiation at about the middle of the antennas ie., the feed point a current node. That is the way I see it, the middle where there is a current maximum. Thus I figure if both antennas are set on a 50' foot mast, then the GM's feed point is close to 11' higher than the Vector and if feed point height affects the results of comparison testing then the GM will start with an advantage. That is why I voted for using the center of the Current Maximums in my thread on Comparing Antennas fairly.

I site a what if example. What if you were going to compare an A99 to a 1/2 wave center fed vertical wire dipole and you were required to compare with the antenna feed points at the same height. The same old story as when we compare a 1/4 wave ground plane and a 1/2 center fed vertical dipole at a 1/4 wave above ground. The 1/2 wave is situated at a disadvantage due to 1/2 the antenna being right at the ground and the same 1/2 being below the feed point. Every time I read such a scenario described, I also hear the same debate about the advantage vs. the disadvantage.

For me this is not important in the normal course of things, but just taking into account what is fair and what is not...when comparing antennas.

I've also heard it said, but I can't be for sure its true, but when testing verticals on an antenna range, it is not uncommon to lay both test antennas on their sides to check things and they can use math models to evaluate elevation issues. Seems that this method of testing claims to remove any elevation differences and truly compares element to element. I could be wrong, because this too could just be more CB BS.

No 007, I don't know of anyone successfully trying to FSM test the bottom of the Vector. I would figure that near field radiation might confuse results, but I can't be sure. I have done field strength testing before, but I generally get as far away as I can and still see a response. I sometimes build an antenna to pickup the signals further away. Most of the time I just use a random wire about 10' feet long if I'm just trying to get and idea about overall radiation and magnitude.

Your thought is rather specific and I'm just not too sure how that would be setup in order to be as discriminating as you might want. You know that nothing in antenna is 100%, so I believe you will have to get really close in order to avoid picking up RF from the larger portion of the antenna and then you may still pick up RF from the center radiator element inside of the cone. IMO I don't see how it is possible. Do you have a game plan?

Keep us posted though.

007, I sure would like to compare the Sigma4 to the GM and that might happen if I have the energy to do all I have planed already. Problem might be however, I only have about 35'+ to work with and the difference in height is about 7'-8' feet. I will have to lower the Sigma and I don't want to get too close to the house with the bottom and have it react badly. I'll see, but my experiences with other antennas suggest that with two antennas, one longer than the other, the shorter antenna will always show equal or better signals with the tips at the same height. Look how the AstroPlane faired against my GM. This is where I get my feed point idea noted above regarding the possible importance of the feed point elevation when comparing antennas.

 

[CTStallion]

On a center-fed, HALFWAVE DIPOLE, maximum current and therefore maximum radiation occurs at the feedpoint. On an end-fed, halfwave antenna, maximum current and maximum radiation does NOT occur at the feedpoint, rather, in the CENTER of the antenna (same as a halfwave dipole).

With a 1/4 wave end-fed vertical, (regardless of type, style, absence or presence of radial elements), maximum current & therefore maximum radiation occurs at the feedpoint.

With a 5/8 (.625) or a .64 wavelength antenna, maximum current & therefore maximum radiation occurs at 1/4 wavelength from the top TIP (end) of the antenna. Even the venerable Sigma IV has it's MAXIMA approx 1/4 lambda from the TOP TIP of the antenna.

Having stated the obvious, the SGM is slightly 'different' because of the capacitor in the radiating element; just as an inductor makes an antenna appear electrically 'longer' to an rf signal, the addition of a capacitor makes an antenna appear electrically 'shorter' to rf (i.e.: CCR Antennas); therefore the current maxima is somewhat S-T-R-E-T-C-H-E-D along the radiator. I'm no electrical engineer by any means, but I believe this is called: capacitive reactance.

Knowing 'WHERE' antennas radiate from makes field antenna testing somewhat more difficult because you CANNOT compare apples-to-oranges; meaning, you cannot compare a 1/2 wave to a 5/8 wave; or a 5/8 wave to a 1/4 wave, or a 1/4 wave to a 1/2 wave. You can only compare APPLES-TO-APPLES. The reason I state this is because if I was mounting all my different antennas on the same 20' mast, they all would be providing maximum radiation from different heights, thereby giving maximum LOS near field advantage to the LONGEST antenna (in most cases). For example, let's look at the height of maximum radiation / current node on the following antennas, all mounted with their BASES on a 20' pole:

- .64 wavelength (24') antenna: (i.e.: Imax 2000): Max rad @ 35' approx
- .625 wave (21-22') antenna: Max rad @ 32' approx
- Vertically Oriented 1/2 wave center fed dipole: Max rad @ 28' approx
- 1/2 Wave End-Fed Vertical (i.e.: Ringo): Max rad @ 28' approx
- 1/4 Wave Vertical (i.e.: Top One, M-400, etc): Max rad @ 20' approx

So, as you can see, there is a 12 - 15 foot advantage in HEIGHT OF CURRENT MAXIMA / POINT OF MAXIMUM ANTENNA RADIATION, with the LONGER antennas to begin with. Mounted on the same pole (at the same height) one would expect them to BOTH hear and talk better (an S Unit(s) advantages in the near field / LOS-Line Of Sight.)

Now, if we adjust the height(s) of antennas in an attempt to "normalize" the readings, for example, raise a 1/4 wave vertical to a height of 32 - 35' to compare it to a .625 or .64 antenna mounted at 20'..... what are we accomplishing??? In reality, if a person could get a 5/8 wave antenna's base up to 35' rather than 20' wouldn't we do that?..... & vice-versa.... if we could get the 1/4 wave up to 35' for the purposes of testing, wouldn't we leave it there to take advantage of it??? Remember.......... ANTENNAS DON'T CREATE POWER, they merely couple it to the ether. The advantage of a .625, or a .64, or a Vector (Sigma IV, Saluit, or LW-150) is that their EXTENDED LENGTH creates a current maxima HIGHER UP THE PHYSICAL MOUNTING POINT. Any 'GAIN' offered in such designs only comes from concentrating the RF 'beam' closer to the horizon.

For LOS (local) work, THE HIGHER THE BETTER IN ALL CIRCUMSTANCES.

For DX (long-haul) work, ANY HEIGHT OF 5/8 WAVELENGTH OR MORE ABOVE GROUND WILL SUFFICE TO PROVIDE ADEQUATE LOW ANGLE CHARACTERISTICS FOR ANY ANTENNA, VERTICALLY OR HORIZONTALLY POLARIZED.

For any VERTICAL antenna mounted BELOW 5/8 lambda from ground, providing adequate ground-loss isolation (decoupling coaxial cable common mode currents notwithstanding) in the form of either ground screens, ground planes, tuned or un-tuned radials, etc., will reduce ground losses and make the antenna more effective. Even if the antenna is mounted at ground level (as many backyard Amateur (Ham) Radio installations are, the DX won't know how high your antenna is. It's getting your lobe where you want it that counts; that's why on the LOW bands, Verticals are superior to horizontal dipoles for DX'ing; because they concentrate their maximum radiation TOA's (take off angles) MUCH lower than horizontal antennas.

Now, if I haven't blown folks' minds enough yet.... here's a fellow who found the A99 superior to the SGM: http://forums.qrz.com/showthread.php?p=2118922

And HIS youtube video appears here: YouTube - Sirio Gain Master vs Antron 99

What do YOU guys think???

 

[Oggy]

A99

On a center-fed, HALFWAVE DIPOLE, maximum current and therefore maximum radiation occurs at the feedpoint. On an end-fed, halfwave antenna, maximum current and maximum radiation does NOT occur at the feedpoint, rather, in the CENTER of the antenna (same as a halfwave dipole).

With a 1/4 wave end-fed vertical, (regardless of type, style, absence or presence of radial elements), maximum current & therefore maximum radiation occurs at the feedpoint.

With a 5/8 (.625) or a .64 wavelength antenna, maximum current & therefore maximum radiation occurs at 1/4 wavelength from the top TIP (end) of the antenna. Even the venerable Sigma IV has it's MAXIMA approx 1/4 lambda from the TOP TIP of the antenna.

Having stated the obvious, the SGM is slightly 'different' because of the capacitor in the radiating element; just as an inductor makes an antenna appear electrically 'longer' to an rf signal, the addition of a capacitor makes an antenna appear electrically 'shorter' to rf (i.e.: CCR Antennas); therefore the current maxima is somewhat S-T-R-E-T-C-H-E-D along the radiator. I'm no electrical engineer by any means, but I believe this is called: capacitive reactance.

Knowing 'WHERE' antennas radiate from makes field antenna testing somewhat more difficult because you CANNOT compare apples-to-oranges; meaning, you cannot compare a 1/2 wave to a 5/8 wave; or a 5/8 wave to a 1/4 wave, or a 1/4 wave to a 1/2 wave. You can only compare APPLES-TO-APPLES. The reason I state this is because if I was mounting all my different antennas on the same 20' mast, they all would be providing maximum radiation from different heights, thereby giving maximum LOS near field advantage to the LONGEST antenna (in most cases). For example, let's look at the height of maximum radiation / current node on the following antennas, all mounted with their BASES on a 20' pole:

- .64 wavelength (24') antenna: (i.e.: Imax 2000): Max rad @ 35' approx
- .625 wave (21-22') antenna: Max rad @ 32' approx
- Vertically Oriented 1/2 wave center fed dipole: Max rad @ 28' approx
- 1/2 Wave End-Fed Vertical (i.e.: Ringo): Max rad @ 28' approx
- 1/4 Wave Vertical (i.e.: Top One, M-400, etc): Max rad @ 20' approx

So, as you can see, there is a 12 - 15 foot advantage in HEIGHT OF CURRENT MAXIMA / POINT OF MAXIMUM ANTENNA RADIATION, with the LONGER antennas to begin with. Mounted on the same pole (at the same height) one would expect them to BOTH hear and talk better (an S Unit(s) advantages in the near field / LOS-Line Of Sight.)

Now, if we adjust the height(s) of antennas in an attempt to "normalize" the readings, for example, raise a 1/4 wave vertical to a height of 32 - 35' to compare it to a .625 or .64 antenna mounted at 20'..... what are we accomplishing??? In reality, if a person could get a 5/8 wave antenna's base up to 35' rather than 20' wouldn't we do that?..... & vice-versa.... if we could get the 1/4 wave up to 35' for the purposes of testing, wouldn't we leave it there to take advantage of it??? Remember.......... ANTENNAS DON'T CREATE POWER, they merely couple it to the ether. The advantage of a .625, or a .64, or a Vector (Sigma IV, Saluit, or LW-150) is that their EXTENDED LENGTH creates a current maxima HIGHER UP THE PHYSICAL MOUNTING POINT. Any 'GAIN' offered in such designs only comes from concentrating the RF 'beam' closer to the horizon.

For LOS (local) work, THE HIGHER THE BETTER IN ALL CIRCUMSTANCES.

For DX (long-haul) work, ANY HEIGHT OF 5/8 WAVELENGTH OR MORE ABOVE GROUND WILL SUFFICE TO PROVIDE ADEQUATE LOW ANGLE CHARACTERISTICS FOR ANY ANTENNA, VERTICALLY OR HORIZONTALLY POLARIZED.

For any VERTICAL antenna mounted BELOW 5/8 lambda from ground, providing adequate ground-loss isolation (decoupling coaxial cable common mode currents notwithstanding) in the form of either ground screens, ground planes, tuned or un-tuned radials, etc., will reduce ground losses and make the antenna more effective. Even if the antenna is mounted at ground level (as many backyard Amateur (Ham) Radio installations are, the DX won't know how high your antenna is. It's getting your lobe where you want it that counts; that's why on the LOW bands, Verticals are superior to horizontal dipoles for DX'ing; because they concentrate their maximum radiation TOA's (take off angles) MUCH lower than horizontal antennas.

Now, if I haven't blown folks' minds enough yet.... here's a fellow who found the A99 superior to the SGM: http://forums.qrz.com/showthread.php?p=2118922

And HIS youtube video appears here: YouTube - Sirio Gain Master vs Antron 99

What do YOU guys think???

This guy I know well, Penn who's a Ham. He sent me the video....and I linked it to mine. It's very puzzling as I have two Mates who swopped an A99 with a SGM (same pole feeder ect ect) and they have seen a great improvement over the A99. Penn said he wasn't too happy with his test and is trying to find a few guys on a Net further away to do some more tests. The truth is I guess 85% of buyers have seen very good improvements over what they use currently. I know I'm more than happy with mine.....as many more are.