New antenna from Sirio Gain-Master

[Marconi]

OK, but according to Masterchief's post, 'the dude' from Avanti claimed the bottom ¼ wave of the Vector style antenna, that "Ice cream cone" thing, doesn't radiate, which I would expect since the currents are of a canceling nature in the base ¼ wave, thus elevating the upper active ½ wave an additional ¼ wave, or 9 feet plus SW's loss of 5 feet = 14 feet down from the Vector's radiator.

- Also, the standard I-10K style bottom/end fed 5/8 doesn't have anything to cancel the base 1/8 of reverse current, except on the Penetrator500 where the highest reverse current is below the elevated radials and sent toward ground instead of canceling as much of the upper in-phase ½ wave as does the 5/8 without elevated radials.

What some have claimed is the Penetrator's downfall, (those darned elevated radials) I believe works to it's benefit.

I won't get involve discussing MasterChief, but some do believe that idea.

That issue about the bottom of the Vector is exactly why everyone got all egg faced when the models presented seemed to indicate the bottom was first in-phase and then not in-phase when Bob's thread got into some modeling presentations. I think we mis-read how and what Exnec was showing when their model displays currents.

I can't claim that my models tell the truth, but they do show the Sigma4 bottom radials are in-phase with the 1/2 wave element above the hoop. It also shows that the 1/4 wave radiator inside the radials is mostly out of phase with the radials and the radiator above the hoop.

SW also just posted a Sirio produced Vector pattern view of the antenna showing an in-phase relationship going-on from top to bottom with a small null just above the hoop. IMO, this confirmed what Bob had been preaching to us for some time, and the topic is also what MC argued against.

The only way I believe the GM would show better signals than a well tuned Vector is if the GM is as high or higher at the tip, and then I'm not sure about if or how the feed point would enter into the mix.

IMO, the beauty of the GM 5/8 wave is in its center fed dipole design and all the advantages of balance and symmetry that provides.

 

[CDX-007]

I won't get involve discussing MasterChief, but some do believe that idea.

That issue about the bottom of the Vector is exactly why everyone got all egg faced when the models presented seemed to indicate the bottom was first in-phase and then not in-phase when Bob's thread got into some modeling presentations. I think we mis-read how and what Exnec was showing when their model displays currents.

I can't claim that my models tell the truth, but they do show the Sigma4 bottom radials are in-phase with the 1/2 wave element above the hoop. It also shows that the 1/4 wave radiator inside the radials is mostly out of phase with the radials and the radiator above the hoop.

SW also just posted a Sirio produced Vector pattern view of the antenna showing an in-phase relationship going-on from top to bottom with a small null just above the hoop. IMO, this confirmed what Bob had been preaching to us for some time, and the topic is also what MC argued against.

The only way I believe the GM would show better signals than a well tuned Vector is if the GM is as high or higher at the tip, and then I'm not sure about if or how the feed point would enter into the mix.

IMO, the beauty of the GM 5/8 wave is in its center fed dipole design and all the advantages of balance and symmetry that provides.

I agree about the beauty of the SGM being in it's balanced design.

As far as what Masterchief told them, perhaps either the person at Avanti didn't really know what was going on or perhaps it works even better than they anticipated...?

I still have a hard time with the idea of those reverse currents not canceling most all radiation from the bottom ¼ wave, though I would agree that those on the cone would be in phase with the top ½ wave, they're still out of phase with the bottom ¼ wave of the radiator element.

I'd certainly like to see about a test done with both tips identical in height with the same run of coax and on the same mast, shoved about 5' higher when the SGM is on top.

 

[Shockwave]

I'm sorry for the confusion with my description of the heights of my antennas. I had to cut 4 or 5 feet off the mast when I installed the GM. That obviously did not put the tips at close to the same height. I think we are paying far too much attention to this minor difference in height for all the wrong reasons. Unless adding a few feet actually makes the difference in clearing a major obstacle that is blocking a particular direction, the effects may be different from what you would expect.

There are installations where removing a few feet of height may help reach stations in the distance. Remember what W8JI said about getting the maximum field strength in the target area. Sometimes changes in height of the antenna have more effect on the angles of the radiation lobes and nulls then on clearing any obstacles. I had a situation where adding 14 feet of mast happened to line up a deep null right at my most important target angle. What a waste of a weekend that was.

That was a long time ago at a different location and I spent a lot of time scratching my head trying to figure out what went wrong. I gained a little signal locally in one direction where a hill about 10 miles away had been blocking my signal. All skywave signals seemed like they were down 15 db from where they were 14 feet lower. It was only after studying the effects of height with computer modeling that it became evident I had shifted a radiation lobe that was important for working DX, down several degrees right into the skirt of a deep null.

Back to the Vector. We must put away the myth that it's any type of end fed 1/2 wave radiator. Look at the CST current plot and ONLY pay attention to the colors that actually radiate away from the antenna. It clearly shows the shielding action of the cone and the cone emitting it's own radiation at the correct phase. Understanding what this one picture means, explains everything that has been missing for 30 years.

The antenna is an unconventional collinear that is based on shielding action rather then cancellation to keep all radiation in the correct phase. No one spoke to anyone who knew anything at Avanti that claimed the cone did not radiate. Bob and myself remember how Avanti advertised the Sigma IV through the 1980's. "Entire antenna radiates" rings a bell in my mind.

I've taken many things into consideration when I say the GM has virtually the same gain as the Vector. My Vector was on a 10 foot mast prior to installing it on the 15 foot mast that I just cut back to 10 with the GM. The Vector gained nothing with 15 feet to stations 50 miles away to my south and east. It picked up the slightest detectable signal increase to the north and west that are at higher elevation then me. When you consider the published gain above a 5/8 wave on both of these antennas, that also says they have virtually the same gain.

Marconi, to answer the question about how I measured signal changes with another antenna 1 wavelength away, I did it with my simple method. I took my VHF receiver out in an open yard with the digital volt meter connected to it's analog meter. I have a 5 foot mast driven into the ground so that only the top swaged section is sticking up. Then I can put a VHF antenna on a 10 foot mast (similar to 36 feet on CB) on top of the ground connected to the receiver.

I took a string one wavelength long and tied it between the first mast and a second mast with an identical antenna and no coax. I tuned in a station at about half signal strength and walked in a circle holding the second antenna mast with the string tight observing the digital signal meter. I'm not 100% sure what direction the signal was coming from but at one point in the circle the signal peaked up strongly. When the passive antenna was moved exactly 180 degrees along the circle, the signal dropped by the same amount it gained. When the passive antenna was moved perpendicular to the axis showing the gain and null, signal levels were very close to when there was no passive antenna in the field.

 

[dxswe]

Wow, that's quite a large difference!

How high were the two antennas mounted above ground, and is there anything such as a TV antenna or large tree in the near field?

What coax type have you?

I have my antenna 15 meters above ground.
The coax cable is a ECOFLEX 10 low loss.
Ecoflex 10

 

[CDX-007]

OK, well, having your antenna ~50' above ground is better than most!

Speaking of coax, I got lucky yesterday and grabbed 150' of this new for $60!! I wish he wanted to sell more!

I just went back and re-read the specs on that ecoflex and I'm seriously impressed! I wish we could get that over here. I misread it, thought those loss figures were for 100' not 100m!

I wonder if it's available in the USA?

What does it cost per meter?

 

[Marconi]

Comparison of GM vs. AP at various heights.

Here is my first GM vs. AP Signal Report that compared my GM vs. AP. The GM being 11' feet higher @ 55' to the tip, and AP @ 44' to the tip. I noticed right away that the GM was stronger both TX/RX and noticeably quieter...to the point that I could almost full copy some stations on the GM that I could just barely hear on the AP. I posted this earlier too.

The second Signal Report below, which I recorded this AM, has both antennas with the tips at 44' feet, where I lowered the GM by 11' feet. I noticed right away that the hearing advantage for the GM went away, and I no longer saw a noise reduction on switching between antennas. Of course conditions could be affect such findings, but in the previous 2 or 3 days I had not noticed any such changes, so I'm not sure why. On RX, the signals were closer together compared to the first report, and experience told me that I should see the AP produce the stronger signals with the tips being equal in height. At this point I started using a "+" or a "-" sign after the Sunits # when I saw signals with a smaller difference.

On the third report, which will follow, I raised the GM up just 5' feet to where the antennas are at equal heights to their centers. I have yet to record and report because conditions were starting to change later in the morning, so that will be a day or two. However, at first notice I saw the RX signals increasing back like previously with the GM and the noise reduction factor seemed to improve as well. The signal report will follow.

I know that most of you are not interested in changing heights for any particular reason, you put them as high as you can and feel good about it. However, I think there might be more to a little change in height than most would guess using the more acceptable way of comparing...using the same mast, coax, and location.

I also accept the possibility that the results I see could be just as Shockwave suggested, a change in height might be associated with different angles and maybe different stuff near the ground to reflect off of in one direction as apposed to another. I can't say that I sensed this among the group I monitored in this process, but I grant that is possible.

After I complete the third report with both antennas at equal current maximums, I will switch the antennas and re-test the antennas and report if I see any differences changing the location, coax, and mast.

Click here:View attachment IMG.pdf

 

[Marconi]

I'm sorry for the confusion with my description of the heights of my antennas. I had to cut 4 or 5 feet off the mast when I installed the GM. That obviously did not put the tips at close to the same height. I think we are paying far too much attention to this minor difference in height for all the wrong reasons. Unless adding a few feet actually makes the difference in clearing a major obstacle that is blocking a particular direction, the effects may be different from what you would expect.

I understand SW. I was just trying to make understanding a somewhat complicated issue more clear. For me, the only time that height is important is when trying to compare two antennas, and that is what I’m trying to demonstrate as clearly as I can in my work. I get the impression with most comparison comments made on the Net, that the subject antennas were compared without any consideration for location, height, or design. Most are just comments, “…my Imax destroyed my A99” or something similar. Otherwise you’re right, antenna height is of little consequence as long as we can talk on our radios.

I said this earlier somewhere, what we thought was a height advantage for your Vector, of maybe 7’-8’ feet, turns out to be an additional 5’ feet. For me that would make a considerable difference, considering your results that the GM, albeit with a 12’-13’ foot disadvantage still produced similar results to the Vector. For me that is amazing!!!

For you guys that live in areas with varying topography you have other issues to consider and I have no experiences at such. My work does not necessarily apply, so your results may differ.

There are installations where removing a few feet of height may help reach stations in the distance. Remember what W8JI said about getting the maximum field strength in the target area. Sometimes changes in height of the antenna have more effect on the angles of the radiation lobes and nulls then on clearing any obstacles. I had a situation where adding 14 feet of mast happened to line up a deep null right at my most important target angle. What a waste of a weekend that was.

I agree with you both in this regard, but W8JI could be focusing on a specific target and I try to focus on a wider scope for comparisons. I’m not even trying to steer or analyze these radios signals I get or transmit. I have never had a similar situation happen to me when raising an antenna up as much as 14’ feet. It may have happened, but I didn't notice it. I have seen plenty of cases where the opposite occurred, at even less height increase, and I noticed that.

That was a long time ago at a different location and I spent a lot of time scratching my head trying to figure out what went wrong. I gained a little signal locally in one direction where a hill about 10 miles away had been blocking my signal. All skywave signals seemed like they were down 15 db from where they were 14 feet lower. It was only after studying the effects of height with computer modeling that it became evident I had shifted a radiation lobe that was important for working DX, down several degrees right into the skirt of a deep null.

My experience in modeling going from 18’-50’ feet high does not typically show me much if any changes in maximum angle, and I don’t suspect I’m steering the angle much either in my real world efforts. I can’t say it is not happening, so I have to agree in principal. However, I do see significant changes in modeling going from about 100’ to 200’ and higher where the pattern and angles do change a lot.

Back to the Vector. We must put away the myth that it's any type of end fed 1/2 wave radiator. Look at the CST current plot and ONLY pay attention to the colors that actually radiate away from the antenna. It clearly shows the shielding action of the cone and the cone emitting it's own radiation at the correct phase. Understanding what this one picture means, explains everything that has been missing for 30 years.

The antenna is an unconventional collinear that is based on shielding action rather then cancellation to keep all radiation in the correct phase. No one spoke to anyone who knew anything at Avanti that claimed the cone did not radiate. Bob and myself remember how Avanti advertised the Sigma IV through the 1980's. "Entire antenna radiates" rings a bell in my mind.

I've taken many things into consideration when I say the GM has virtually the same gain as the Vector. My Vector was on a 10 foot mast prior to installing it on the 15 foot mast that I just cut back to 10 with the GM. The Vector gained nothing with 15 feet to stations 50 miles away to my south and east. It picked up the slightest detectable signal increase to the north and west that are at higher elevation then me. When you consider the published gain above a 5/8 wave on both of these antennas, that also says they have virtually the same gain.

I’m not sure how the Vector and the typical 5/8 wave really compare with gain, but I can’t say that I ever noticed changes in signals on raising my other antennas up 5’, 10’, or 15’ feet like you say, until I saw this GM respond to my AstroPlane with it first 11’ feet higher compared to it being just 5’ feet higher and for sure with the GM being at the same tip height with the AP, where it was a toss-up. I also can’t make the same statement for the AP, it I was moving it around either, so even though I see the GM making significant differences in signals, and RX quality here, it only does so when I get it up higher above the other antenna. In that case, I can only speculate that height is important. I also see the GM responding what I would call “…giving a bad response when mounted less that 18’ feet. So this whole issue is confusing and makes me curious.

Marconi, to answer the question about how I measured signal changes with another antenna 1 wavelength away, I did it with my simple method. I took my VHF receiver out in an open yard with the digital volt meter connected to it's analog meter. I have a 5 foot mast driven into the ground so that only the top swagged section is sticking up. Then I can put a VHF antenna on a 10 foot mast (similar to 36 feet on CB) on top of the ground connected to the receiver.

I took a string one wavelength long and tied it between the first mast and a second mast with an identical antenna and no coax. I tuned in a station at about half signal strength and walked in a circle holding the second antenna mast with the string tight observing the digital signal meter. I'm not 100% sure what direction the signal was coming from but at one point in the circle the signal peaked up strongly. When the passive antenna was moved exactly 180 degrees along the circle, the signal dropped by the same amount it gained. When the passive antenna was moved perpendicular to the axis showing the gain and null, signal levels were very close to when there was no passive antenna in the field.

I think I’ve asked you that before, and you responded similarly. Thanks.

Here are my antennas with the GM about 5' higher than my AP. Sorry if the picture distorts the images a bit. I had to go about 3 houses down the street to get them in the open thru the trees. I tried to get as square as I could without going in my neighbors back yard.

 

[Oggy]

Well Well Well!!!!

I've been watching your results with interest..............I guess I wasn't talking BS after all.......LOL

 

[CDX-007]

Marconi, I'd like to see you fill your worksheet with both tips at equal elevation, then remove the AP all together and double-check the SGM with the same stations to see if there was any change in signal strength.

I wonder if one is using the other, even though separated by 35', as either a reflector or a director, especially when lined up at the same height?

 

[1342]

hello guys there is a couple things here that dont 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.

 

[CDX-007]

hello guys there is a couple things here that dont 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.

As far as the testing distance, it depends what you're testing for.

If you tend to talk 50-100 miles then that's where the test should be focused.

If you mostly talk around town 2-15 miles then closer results are more important.

I like to test at all distances possible, but I agree, the further out the better if long local/DX is your interest, as it is mine.

I also agree about your comment regarding the inherent advantage of a tall antenna over a shorter one. Not that it's not cool to know what is the design efficiency in comparison to another, but in the end you only have so much mast height to work with so the antenna offering the best performance, even if it's mostly due to it's height advantage, is still the overall winner in most real-world installations.

 

[bob85]

we got our first test of the gainmaster vs the sirio top-one mounted on the same mast/feedline at distances from 13-17 miles atcf this evening,

i see 1.5 s-units increase on the icom 703 and i10k,
frogger reported 1.5 s-units on his ft847 and imax,
another local sees 1/3rd s-unit on his icom 7600 and old style vector, another local also sees a similar increse on his stalker iv and a99,

the owner of the gainmaster reports 1.5 s-units increase in my signal and almost 2 s-units in froggers signal on his icom 756 pro2,
he also says there is notably less noise in his receiver making us easier to listen to,

mounting them straight to the mast causes the top-one to be about 15foot lower at the tip than the gainmaster,

strange results considering that the ft847 meter is very happy, usually the ft847 shows a much bigger increase in s-units vs my icom whenever somebody changes transmitter power.

 

[BOOTY MONSTER]

has there been a comparison yet with the GM and another 5/8 or .64 WITH PROPER GROUND ELEMENTS using the same mast height/coax and location ?

 

[CTStallion]

has there been a comparison yet with the GM and another 5/8 or .64 WITH PROPER GROUND ELEMENTS using the same mast height/coax and location ?

PERFECT QUESTION!!!!!!!..... because (as we all know), an antenna can NOT "CREATE" power <gain>, rather, focus the wave. If the GainMaster has any gain at all relative to it's 5/8 wave or .64 wave peers, it could ONLY possibly come from TOA (take off angle) aka: angle of radiation or launch angle.

BTW: My initial thoughts about the British GainMaster tests were that the gain from the Sirio GainMaster were due to it having NEW coax, vs. the 'old' (& possibly lossy) coax on the Shakespeare Army Stick; but, alas, they tested the coax loss on one of the vids and found no improvement on the GainMaster's coax.

I'll tell ya... this one has me stumped :headbang Maybe Sirio has TRULY invented something 'new' in the field of monopole vertical antennas..... I'll be watching op: and learning and, who knows...... maybe (if I was a "good boy" this year) Santa will bring me a GainMaster?????........... naaaaah... who am I kiddin?!?:wub:

 

[Oggy]

Well Well Well!!!

PERFECT QUESTION!!!!!!!..... because (as we all know), an antenna can NOT "CREATE" power <gain>, rather, focus the wave. If the GainMaster has any gain at all relative to it's 5/8 wave or .64 wave peers, it could ONLY possibly come from TOA (take off angle) aka: angle of radiation or launch angle.

BTW: My initial thoughts about the British GainMaster tests were that the gain from the Sirio GainMaster were due to it having NEW coax, vs. the 'old' (& possibly lossy) coax on the Shakespeare Army Stick; but, alas, they tested the coax loss on one of the vids and found no improvement on the GainMaster's coax.

I'll tell ya... this one has me stumped :headbang Maybe Sirio has TRULY invented something 'new' in the field of monopole vertical antennas..... I'll be watching op: and learning and, who knows...... maybe (if I was a "good boy" this year) Santa will bring me a GainMaster?????........... naaaaah... who am I kiddin?!?:wub:

I'm glads somebody mentioned this.......that's WHY I showed the losses because lets be honest.....many cynics wants this antenna not to work.....I along with Scott on here spotted a winner prior to anyone even trying the SGM. When are the Big Buck American so called .64 going to prove it wrong ??....I realy want to see these tests . ....then maybe people will realy believe this is a worthy contender.......like I know it is . It could maybe be time for some antenna designers and builders to sharpen their pencils?