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New antenna from Sirio Gain-Master
- Thread starter dxswe
- Start date
That's right Homer.
My place is about 70' feet above sea level, but it sure looks flat all around me. I can't tell the difference. So, as is often said around these parts, "...it's as flat as a flitter" over this 600 sq miles, Houston on the Texas Gulf Coast.
I've heard and used that expression many times. Maybe I'll return there someday to stay. It's still my hometown.
Being a 5/8λ I figure the Gain Master should outperform the A99, but we know location also matters. So I am kinda neutral on the outcome of your tests, as I know it really doesn't speak to the whole story of antennas. Too much matters that is uncontrollable. But that's been said so many times already.
As I've said, I may homebrew one sometime. I just want to see a photo of the point at which the capacitor and stub are integrated into the antenna. The diagrams are great, but I've never done one like this, so I want it to be just right. Should I build one, then I'll add it to the list of comparable antennas at my QTH.
Being a 5/8λ I figure the Gain Master should outperform the A99, but we know location also matters. So I am kinda neutral on the outcome of your tests, as I know it really doesn't speak to the whole story of antennas. Too much matters that is uncontrollable. But that's been said so many times already.
As I've said, I may homebrew one sometime. I just want to see a photo of the point at which the capacitor and stub are integrated into the antenna. The diagrams are great, but I've never done one like this, so I want it to be just right. Should I build one, then I'll add it to the list of comparable antennas at my QTH.
Marconi, how's the new 3' higher altivation? Any noticeable improvement?
Homer, I bet Shockwave should have the cap value and I measured about 11' 2" from center up/down, and ~24" of shorted coax stub at the feed point.
Not sure which coax their using for the stub.
Homer, I bet Shockwave should have the cap value and I measured about 11' 2" from center up/down, and ~24" of shorted coax stub at the feed point.
Not sure which coax their using for the stub.
Finished with A99
Here is my last report for the A99 vs. Gain Master. I removed the radials and all signals remained the same for the A99. I also made an analyzer and SWR bandwidth curve. The A99 without radials showed a broader bandwidth using the analyzer from from 2.4 mhz to 3.41 mhz. The SWR curve also showed the bandwidth increase for the A99 without radials from 3.2 mhz to 3.7 mhz. This again confirmed what I had recorded for the A99 back in the 90's. So, even though I can't detect any differences adding radials to the A99, there is no doubt something going on or we wouldn't see this change.
In my considerations on matched performance vs. non-match performance among the few antennas I work with and within reason I mostly find similar responses wether the antenna is tuned well or not...the simple act of tuning is almost an undetectable advantage considering the human perceptions of on-air performance comparisons.
Gain Master average Sunits = 7.4
A99 w/o radials = 7.2
View attachment Gain Master vs. A99 no radials.pdf
Yes 007, the extra 3' feet that I raised the GM up to yesterday made a little difference. I got the top of both mounts to 33' 8", as high as one of my poles will go, and I actually recorded a couple of stations showing a 1 sunit differences in favor of the GM.
Here is what is next. I ran out of energy so I'll get the I-10K up all the way soon.
Here is my last report for the A99 vs. Gain Master. I removed the radials and all signals remained the same for the A99. I also made an analyzer and SWR bandwidth curve. The A99 without radials showed a broader bandwidth using the analyzer from from 2.4 mhz to 3.41 mhz. The SWR curve also showed the bandwidth increase for the A99 without radials from 3.2 mhz to 3.7 mhz. This again confirmed what I had recorded for the A99 back in the 90's. So, even though I can't detect any differences adding radials to the A99, there is no doubt something going on or we wouldn't see this change.
In my considerations on matched performance vs. non-match performance among the few antennas I work with and within reason I mostly find similar responses wether the antenna is tuned well or not...the simple act of tuning is almost an undetectable advantage considering the human perceptions of on-air performance comparisons.
Gain Master average Sunits = 7.4
A99 w/o radials = 7.2
View attachment Gain Master vs. A99 no radials.pdf
Yes 007, the extra 3' feet that I raised the GM up to yesterday made a little difference. I got the top of both mounts to 33' 8", as high as one of my poles will go, and I actually recorded a couple of stations showing a 1 sunit differences in favor of the GM.
Here is what is next. I ran out of energy so I'll get the I-10K up all the way soon.
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Eddie, you may also want to try your test with the other antenna not in the air, doesnt look like you have them very far apart and there may be some mutual coupling between antennas. Nothing like eliminating every variable when testing.,
Thanks, Mr Bond.
Call me James. :tongue:
I have to take down & apart the other SGM so I'll take infinitely accurate measurements. I'll try to locate the type of coax in use for both the feed line/element and the other type they're using for the DC shunt.
If Shockwave could point us in the right capacitor value direction...
Marconi, WOW, a full S-unit on one station from an additional ~3' of eletude!?!
I hope you can get it to a point where it's superior performance shines for you, too@!
MrSuburban, after I got my signal reports finished for the A99 vs. GM I was hearing only local traffic, we had no skip today, so I spent several hours recording signals for the GM, up there by itself. However, there were only 5 guys on my contacts list that were still talking, so the report will be incomplete. I have been testing 7 of my best and most reliable regulars. All the signals but Larry's were right on the money, being the same for the GM when I tested it the other day...all by itself on the new mount by the shack.
You are also right, they are 35' feet apart exactly, but that still may be too close. This, and noise is why I'm going to remove this mounting station.
The only thing I haven't tested yet on both mounts is the Top One mounted on the new mount. I know now that this new mount is at least quieter, probably being as it is further away for my power lines. I don't see any difference in signals otherwise, but I do like the "Quiet."
I won't keep the I-10K up very long, because it's heavy and even though the shack mount looks brand new its not as strong as the older mount out back. The I-10K really needs a tower mount to support its solid construction.
I'll put my Top One back up with a new 12' x 1.25" aluminum mast. I've tried it with a 10' x 1.25" and a 97" x 1" x 1" square tubing was last. I was trying to see if mast length and size made a noticeable difference. I haven't compared my Antenna Work Sheet Reports with SWR and analyzer bandwidth curves yet, but nothing really stuck out as obvious concerning these different mast sizes so far. Bob suspects the AstroPlane mast size may have such and effect, so I'll continue to test for the idea.
I may have posted it already, but right now the I-10K is about 2'-3' lower than the Gain Master, and the GM is showing pretty small, but consistently better signals as a result. I have not started recording for the reports however, just checking out truck drivers on 19. Maybe tonight some of the guys will be on the air, and I'll check again.
Now to get some rest.
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Well 007, at this point any signal that is not close to the same on switching or when the antenna is standing alone, is encouraging for me. I really don't like disagreeing with everyone, but I post the info I see. I also like the idea of win, loose, and tie.
Thanks 007, if you do that for Homer then I won't have to.
My GM and my I-10K are likely coming down before the weekend. I may check out the noise difference with the GM vs. the Top One on opposite mounts first however.
When I first started comparing the GM I really thought is was wonderfully quiet, but now I find it's not quite so obvious, because when I put it on my old mount out back I noticed that the mount may be the culprit...and is a bit noisy. It probably is not a great antenna characteristic of the GM that others should also sense...like I initally thought.
007, I really think you'll agree I ought to be checking my stuff out based on the truth...as I see it. Not just try to make the performance shine. I think we already get enough shining-on from some of our professional type "One Liner" CB'er buddies...casting their biased comments with no evidence of any work. I like to see something I can chew on a bit. Maybe I have a Missouri gene in my DNA.
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Thanks for all the effort in testing, even thought I am sure it is fun, it is still work. Wish I could retire and work on antennas everyday, Lucky SOB.
When I look at the beauty of Sirio's CST on that Gain Master I can't help but expect it to shine, and out-shine any other monopole, I'm just hoping yours delivers all it can for you so you'll be getting the most out of your station omni.
Looking at the CST on the GM and trying to compare it to the one picture of the Vector won't be accurate unless you know the phase of the one picture of the Vector. If you look at the GM CST you will see in the interactive pictue the phase numbers are changing you would have to know at what phase the CST of the Vector is to make a comparision.
Please understand that the engineers at Sirio are not idiots. Mr. Lorenzo provided the CST image and it's almost insulting that you guys would think he wasn't bright enough to send me an image showing the radiation at one of the two maximum current points. Any other phase angle shown in a still image would be useless. Give us a little more credit then that please. If looking at that image does not give you a clear indication of how the antenna works, perhaps reading about how CST works will help.