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 One for Steve.......Sirio Gain Master 
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Post One for Steve.......Sirio Gain Master
Seems to be a lot of interest/hype in this Steve.....may I have your opinion ? Came across it while looking for a replacement for my old A99 for 10m. :?:

http://www.pjbox.co.uk/product/ANT-Siri ... /3799.html

http://www.gain-master.it/PD%20Gain%20M ... 7-2010.pdf

http://s3.zetaboards.com/copythat/topic/7427206/7/


Some interesting youtube video's on tests that people have done.

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Thu Nov 25, 2010 11:04 am
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 One for Steve.......Sirio Gain Master 
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Post Re: One for Steve.......Sirio Gain Master
Quote:
It has a exceptionally bandwidth (see Fig.8) of over 4.5MHz..... from 25.5 to 30MHz


Sounds like a dummy load.


Thu Nov 25, 2010 2:45 pm
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 One for Steve.......Sirio Gain Master 
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Post Re: One for Steve.......Sirio Gain Master
i know your probably after a technical explination from steve but i thought id add my penneth worth.. there was a debate on here a while back re the i max which has similar bandwidth. when all said and done and the debate was over the fact was the guy still made decent contacts on it .. im sure you would with that

for me i couldn't justify the price tag, and to be honest a good old silver rod would be my choice.. 1, because im tight and 2 , because they work very well , ok you don't get a huge bandwidth but thats down to them being simply matched for the 10/11 m band..

£18 or £120 odd ,i know which id go for ..

billy

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Thu Nov 25, 2010 4:04 pm
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 One for Steve.......Sirio Gain Master 
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Post Re: One for Steve.......Sirio Gain Master
i use a sirio 827 for local chats & euroland :lol:

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Thu Nov 25, 2010 4:12 pm
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 One for Steve.......Sirio Gain Master 
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Post Re: One for Steve.......Sirio Gain Master
There are some very bold claims being made about this new offering from Sirio, some which just don't stack up. I've not seen one or had one apart, but from what I have seen it's a half wave dipole in a fibreglass case with a coax choke below it, that doesn't sound anything special to me, that said, some guys are claiming it's a huge imrovement, over similar antennas, with their back to back field tests, the jury's still out at my QTH at the moment.

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Thu Nov 25, 2010 5:43 pm
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 One for Steve.......Sirio Gain Master 
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Post Re: One for Steve.......Sirio Gain Master
Seems I am not the only one to question the claims, but watching some of the you tube video's it seems to work quite well. It is claimed to to 5/8 wave. Looks to me like a vertical centre using the coax as the bottom half and then the choke to stop cm. It looks almost to good to be true on the video, some of the signals go up 3 s points over a big stick.

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Thu Nov 25, 2010 5:57 pm
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 One for Steve.......Sirio Gain Master 
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Post Re: One for Steve.......Sirio Gain Master
' 0.625 centrefeeded vertical dipole'

thats what it says in the blurb.

the Italians grasp of English as accurate as ever..........................
:roll:

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Sat Nov 27, 2010 9:48 am
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 One for Steve.......Sirio Gain Master 
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Post Re: One for Steve.......Sirio Gain Master
and the lack of a definitive gain figure is a little suspicious too.
1-2 db over a conventional 5/8 wave on the horizon?

hardly dbi or dbd now, is it?

aaaaaahhhhhhhhhhhh I get it now, if you read the blurb on sirio's website, it states the maximum gain is perfectly horizontal, hence the 'more gain on the horizon' statement.
but that is going to detract from the angle you need for successful ionospheric propagation, isn't it?

all of the tests on the link are with 'local' stations, I'm guessing the Shakespeare and Vector4000 comparisons would be different on a signal arriving at a different angle, ie above the horizon, ie 'DX'.

want to talk local?
get a GAINMASTER.

want to 'shoot skip'?
stick with your 827, Vector4000, Imax, Antron, 5/8 Silver Rod.

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Sat Nov 27, 2010 10:24 am
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 One for Steve.......Sirio Gain Master 
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Post Re: One for Steve.......Sirio Gain Master
Apologies for the delayed response - I've just returned from a few days in Bruges/Brussels.

As best I can see from all the literature it's a centre-fed 5/8 wave vertical; it uses the outside surface of the coax for the bottom half of the antenna. The capacitor will help the matching by compensating for the inductive component of feedpoint impedance which is caused because the antenna is longer than a half-wave. I'm not sure about the S/C stub - no details are given - but it may help with extending the VSWR bandwidth; it wont change the radiating characteristics.

There's no "magic". A centre-fed 5/8 wave vertical will have about 0.25dB more gain than a centre-fed 1/2 wave vertical dipole at low take-off angles. I don't see anything that would justify the claim for 2dB gain over a conventional 5/8 wave.

I was amused by the focus in the U-Tube video on the 50 Ohms analyser reading even when the reactance was high. The guy didn't seem to realise that what he was measuring was not the antenna impedance - with a 1.9:1 VSWR the antenna impedance could easily have been 95 Ohms or even 26 Ohms!!!

Steve G3TXQ


Mon Nov 29, 2010 12:07 pm
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 One for Steve.......Sirio Gain Master 
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Post Re: One for Steve.......Sirio Gain Master
I can't help but think some people are too willing to accept CB antenna manufacturers claims, gain figures are quite often over estimated, whetever takes place in the fiberglass tube isn't going to change the laws of physics.

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Mon Nov 29, 2010 2:09 pm
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 One for Steve.......Sirio Gain Master 
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Post Re: One for Steve.......Sirio Gain Master
true. but the average person who goes for this type of antenna(£120) ? is a CBer, who has no or little knowlege of gain etc.
and the manufacturers know it. "that looks nice, it must be good"
why has the antron 99 junk sold in millions when a £23 5/8 silver rod works better DX?


Sun Dec 05, 2010 9:58 am
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 One for Steve.......Sirio Gain Master 
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Post Re: One for Steve.......Sirio Gain Master
G3TXQ wrote:
Apologies for the delayed response - I've just returned from a few days in Bruges/Brussels.

As best I can see -------------------------

-------I was amused by the focus in the U-Tube video on the 50 Ohms analyser reading even when the reactance was high. The guy didn't seem to realise that what he was measuring was not the antenna impedance - with a 1.9:1 VSWR the antenna impedance could easily have been 95 Ohms or even 26 Ohms!!!

Steve G3TXQ


I noticed these different readings Steve and wonder what the implication was, or how the VSWR remained low, I'm making the assumption that the VSWR remained low due to loss in the system and that the antennas efficiency is seriously compromised once it gets beyond resonance, what is the implication of a high reactive component?

thanks
Stephen

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Sun Dec 05, 2010 3:36 pm
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 One for Steve.......Sirio Gain Master 
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Post Re: One for Steve.......Sirio Gain Master
Stephen,

My comment was aimed at the fact that the guy in the video seemed to think it was a "good thing" to have an impedance of 50 Ohms Resistive, even when the Reactive component was high; that shows a lack of understanding about how transmission lines work.

If I measure R=50/X=30 (VSWR=1.8:1) on my analyser at the shack end of the coax, the antenna impedance could be:

R=50/X=30
R=82/X=20
R=90/X=0
R=50/X=-30
R=28/X=0

to name just 5 of the infinite range of impedances it could be, depending on the length of the coax.

There's nothing commendable about an analyser reading of R=50 without regard to the X component.

Steve G3TXQ


Sun Dec 05, 2010 7:23 pm
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 One for Steve.......Sirio Gain Master 
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Post Re: One for Steve.......Sirio Gain Master
So if I'm learning anything, the increase in reactance will increase loss in the system, and would manifest itself in heat if run at the manufacturers maximum limits, the manufacturer stating it is capable of 500w CW and short time CW 1000w.

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Sun Dec 05, 2010 8:33 pm
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 One for Steve.......Sirio Gain Master 
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Post Re: One for Steve.......Sirio Gain Master
Hello all, and what a good Forum you run. Been a Newbie on here go steady on me. I was the very Man who did the Youtube videos of the new Sirio Gain Master antenna. As I pointed out to Steve I showed the MFJ analizer mainly for the bandwidth and the VSWR curve on the CB/10 Meters Ham band. Showing it @ 50ohms impedance was not the best way I know. I know a lot of Radio Hobbyists who use the CB Band and I didn't want to get too technical about the tests or KISS as the saying goes. I may do a further video with MFJ at some point ,with more details, but I do think I got the point over that the new Sirio Gain Master is not "Snake Oil". Nearly every one I know who has replaced their current 5/8 Wave End Fed Monopole has seen big improvements.
I read about the antenna on Sirios website and rather than been Cynical and an Armchair Expert,I thought I would take "The Bull By The Horns" and test it against my Shakesphere ABS1600 ABS that's a known good peformer.To be fair I thought it wouldn't be a big improvement. But my findings say otherwise
Next Spring I will do a same pole ,feeder test, as some have mentioned this to be a better route, but I still think I will find the same. I also feel many CB antenna companies tell a few fibbs for sure, but Sirio with their R&D Team who have degrees in RF Technology and the use ot a $1 Million USD shielded Anechoic chamber to test their products are some of the best with their claims I feel.....Thanks for taking the time to read my post......73's De Dave M0OGY North Lincolnshire.


Mon Dec 20, 2010 8:02 pm
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