New antenna from Sirio Gain-Master

[Oggy]

eddie/dave,
my mate cranked it up to 750w fm on his welz meter for a while last night and still no arcing,
theres something odd going on when a kl203 which at best will make about 130w is destroying an antenna that seems to be able to handle 500w fm and more on lower duty cycle modes,

hes had no problem with 100w from his icom pro2 or 200w from his 1000mp markv and so far no problem with over 500w fm or 800w ssb from his 3-500z's

nothing special was done when he assembled the gainmaster other than spending some time straightening the coax / wire so it pulled straight and pushing the stub straight down inside the tube with a rod.

Well I had the same here........I had mine up to 600 watts FM keydown into an Antenna Solutions digital power meter thats nearly £400 worth and far more accurate than a £50 CB unit. The main reason was the SWR alarm function to be honest I took 2 hours to build mine as i'm a bit OCD with tape measures ect. But followed Sirios instructions to the "T". Mine has the silver nipple on the "Pigtail".I have not had anyone contact me or indeed leave anything on my Review Videos of theres failing. I guess time will tell Mate

 

[CDX-007]

I for one don't have an issue with questions on the CT site......and I'm a very early member (N0 10 out of over 600). I think the first thread was shut down as it went off topic a little. As you see a second thread is going strong. As for power findings as I posted a day or so ago after Simon said his had let go . I have a good few Ham HF linears that can create over 1KW. But these are built in my Ham shack and at over 25KG way to heavy to take in my CB shack. I found out my Dads old 1980 CTE Galaxy 1KW CB/10 Meter Oldskool mains tube amp and with an Antenna Solutions digital Power meter with an alarm function preceded to crank the power up to the recomended FM rating.....I left it keyed for 5 minutes on and off and tried it all night.I had no issues with my SGM at all under these conditions. My model is a fairly early one that came direct from Sirio in Italy and has the nickle plated nipple on the end of the "Pigtail". So I guess we'll see what Sirio find. I am sure any problematic ones will be sorted quickly and FOC by Sirio as I do know they do listen to feedback and don't hide their heads in the sand. Again Marconi ,keep the tread going "Over The Fence" so to speak......I enjoy yours ,Scotts and others input.....This antenna has caused quite a stir for sure!!

Yes Oggy, I find it the most intriguing thing to happen to 11m in decades. I love antennas and antenna theory so seeing a company implement an old idea in a way which exemplifies logistics which have gone unused until now is very exciting for me and is certainly stirring things up!

I guess I'll have to fire up the 4-400s and hit it with .5kw for about 10 seconds to make sure mine is a good one. - Could be a run of bad caps.

Hey Shockwave, have you the capacitor value?

My computer was down for all of last week. I hope you'ze guyz enjoyed the break!

 

[okiebob]

I just want to take a few minutes here to say how impressed I am with this web site and this thread.
I took the time to read it all from start to finish and have gone back through it a couple of time to
make sure I had a understanding of what was being said.
What impressed me the most was how most all have did there best to prove or disprove this antenna claims by physically doing the leg work and making the adjustments.
To quote theory means little to a old CB'er like myself, I need the facts right off the masts.
To quote some theory and say the antenna is all bull crap does little to prove what's right, wrong
or working.
I won't name names cause I can't remember all you, but you know who you are and you all should give yourselves a pat on the back. You all made this a very enlightening thread.
Once again great job to all of you .
Have a Merry Christmas and a Happy New Year.

 

[Oggy]

Thanks

I just want to take a few minutes here to say how impressed I am with this web site and this thread.
I took the time to read it all from start to finish and have gone back through it a couple of time to
make sure I had a understanding of what was being said.
What impressed me the most was how most all have did there best to prove or disprove this antenna claims by physically doing the leg work and making the adjustments.
To quote theory means little to a old CB'er like myself, I need the facts right off the masts.
To quote some theory and say the antenna is all bull crap does little to prove what's right, wrong
or working.
I won't name names cause I can't remember all you, but you know who you are and you all should give yourselves a pat on the back. You all made this a very enlightening thread.
Once again great job to all of you .
Have a Merry Christmas and a Happy New Year.

It's very nice for somebody to praise the many hours spent by the WWRF guys and others who have spent many hours testing this antenna. I was the first in the UK and indeed spent 4 weekends conducting my review/tests on the Sirio Gain Master.I'm also the member who put four in depth review videos on Youtube. This is one of the very few CB Radio products that does what it says on the tin and (in my eyes) not just clever marketing and BS..The UK Waving a Hand, and Happy Christmas........Dave M0OGY/26CT110 North Lincolnshire UK.

 

[CDX-007]

...and I 2nd that!

Just one thing I've discovered in testing these two SGMs... it needs to be in it's own space.

It's a center-fed dipole and as such is a balanced antenna so it needs to be kept away from anything metallic or resonant which could upset the balanced pattern.

Sirio isn't kidding when they say to keep it at least 3-6 meters above the roof, or anything else which could throw off the balanced pattern!

Those who find it a poor performer in comparison to their 'other' antenna have probably not given it the space required for it to shine. This really is new technology and a great idea with regard to propagation of signal!

I'm loving mine!

 

[hotrod]

well after 30 some pages just wanna say thanks also for the testing
i find it very interesting and helpful.is it safe to say the SGM is king
of fiberglass antennas. and can equal the p500?

 

[CDX-007]

As long as you don't need it to handle more that ~500w-1000w pep and can install it well above and away from all other objects, it should keep up with or outperform almost ANY vertical omni.

 

[MrSuburban]

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.

The feed point height makes the most difference not tip height any modeling program will show this to be true. Any change in feed point height will change the pattern.

 

[okiebob]

The feed point height makes the most difference not tip height any modeling program will show this to be true. Any change in feed point height will change the pattern.

So what your saying is if you put a I-max 2000 on a 40 ft mast and the new
Gain Master on a 30 ft mast the playing field is closer to equal.

 

[mackmobile43]

The feed point height makes the most difference not tip height any modeling program will show this to be true. Any change in feed point height will change the pattern.

By this statement wouldn't that mean comparing any one antenna to another equates to :headbang and should be avoided?

 

[hotrod]

By this statement wouldn't that mean comparing any one antenna to another equates to :headbang and should be avoided?

ive always checked base antennas at same pole/tower height
same location,same coax ,so the ONLY a change is the antenna
mounting one higher than the other .the one mounted higher
should win every time id think .cause height = might thats why
i mount them the same height and everything else the same
this elimates the variables .well ones i know of anyways..lol

 

[CDX-007]

The feed point height makes the most difference not tip height any modeling program will show this to be true. Any change in feed point height will change the pattern.

Makes me wonder if there's a way to mount the Imax upside down so the feed point is on TOP... :blink:

Are you comparing antennas or mast height?

If you compare a ½λ dipole to an end-fed ½λ and placed the two feed points equal, the one with the bottom end feed point would always have the benefit since it would always be taller, however, when you mount a bottom-fed Imax or Penetrator on the same mast & height as the Sirio Gain Master center-fed 5/8 dipole, the SGM still wins.

Perhaps we can draw from this that all center-fed antennas of similar wave portion are superior to end-fed?

I don't consider that a benefit of the feed point as much as a benefit of the overall design allowing the out of phase end current to be realigned into non-destructive helpful current now in the center.

If it were feed point height alone that dictates performance, simply turn the end-fed 5/8 design upside down and you'd then have the feed point on top, (you can't get higher than the top!!) - but would it then outperform the center-fed Sirio because the end-fed 5/8 feed point is now on top?

NO, because the top-end-fed 5/8 still produces the same out of phase end current as does the bottom-end-fed 5/8 even though the feed point height would be as high as possible.

So it seems to me that it's not just about the feed point height, it's the entire design that either performs or doesn't.

 

[CDX-007]

So what your saying is if you put a I-max 2000 on a 40 ft mast and the new
Gain Master on a 30 ft mast the playing field is closer to equal.

Or how about, "You only need a 30' mast for your SGM in order to keep up with your neighbor's Imax & 40' mast" ...?

 

[okiebob]

Or how about, "You only need a 30' mast for your SGM in order to keep up with your neighbor's Imax & 40' mast" ...?

I was just trying to get a grasp on what was posted a couple of threads above.
But your thread above this one cleared up a lot.
Just from what I have read here I feel the Gain Master may be
a little better than some of the bottom loaders out there.
I haven't bought one yet but I'm giving it some thought.
My biggest worry is mounting it above a 4 element beam.
From what I have read there might be some concern mounting
the GM to close to other antennas.

 

[CDX-007]

I was just trying to get a grasp on what was posted a couple of threads above.
But your thread above this one cleared up a lot.
Just from what I have read here I feel the Gain Master may be
a little better than some of the bottom loaders out there.
I haven't bought one yet but I'm giving it some thought.
My biggest worry is mounting it above a 4 element beam.
From what I have read there might be some concern mounting
the GM to close to other antennas.

I would expect that to have issues with upsetting the balance of the balanced design, causing a higher TOA than expected.

In such an installation I would probably prefer the Imax.

I've found the SGM to need it's own free space in order to reap the maximum rewards of it's design.

Mine currently resides directly above my 80m inverted vee and I can tell it's lost some of it's zest compared to when it was alone in the sky.

..."To the trees, to the trees!"