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Looks like a typo, his recent sales were for $12.99 ;)

I think he's trying to exhibit worse case senario with his choice of mast length, and not connecting it to ground isolates the poor length choice, as he mentions such in his follow up article about the Imax 2000: He goes on to explain why the models are in freespace: I also noticed the...

I'm a bit of a cheapskate and I'm using MMANA GAL Basic at the moment, a lot more facitities than the free version of Eznec, but at the same price :) but the cheapskate in me is fighting a losing battle with the Ham inside me that says spend a little and pay for Eznec, time will tell, I've got...

Interesting results, I wish I'd saved my models in the same way, if I get chance over the weekend I'll attempt similar ;)

I spend most of my radio time working mobile (amateur frequencies) and one way to increase efficiency, and bandwidth, is to add a capacitance hat to a shorter than 1/4WL mobile antenna, with this in mind and if the ring does indeed increase bandwidth, then the case for capacitance is looking...

I decided to do some rudimentary modelling in MMANA, I took a standard 5/8 WL model that I use as a basis for antenna construction and extended the element to 3/4WL, as predicted the gain increased, however that gain was at pretty useless angles, a fundamental problem with a 3/4WL monopole, I...

Hopefully the link works, I can't access it from work: Backyard wire antennas

A couple of posts further up I again questioned the science behind the Sigma 4 success, not knowing what made it such a high performance antenna, looking at the CST graphic I postulated that the outsied of the basket is in fact radiating and the inside of the basket contains opposing currents...

I think some of the modelling shortfalls with Eznec may be as a result of the NEC 2 engine, the later professional version of Eznec is NEC4 based, however unless you're a wealthy man it's a bit expensive as you need both a NEC4 licence and the Eznec licence. I came across this issue when...

The currents inside the cone are equal and opposite, the antenna mast and the current on the inside of the basket are contained within the basket, similar to coax in a balanced mode, however the additional current on the outside of the basket is similar to common mode current on coax, however in...

The reason a coax cable works is due to the opposing currents carried along the outer of the centre conductor and the inside of the outer screen, any current on the outside of the screen, CMC, will radiate, this is why coax can sometimes be called unbalanced. Twin feeder cable carries...

I know a few of the chaps on here have a fair bit of experience with the Sigma 4, Vector variants, and home brew works of art, and I'm prepared to take your various experiences of working with the antenna as proof of the pudding, but I would like to know the essence of what makes this antenna so...

You're welcome to pop round anytime, it's a bit of a drive though:D I already have the tower, it's a four section 60' Strumech, the only downside with the UK is that I have to apply for planning permission from the local planning authority, fortunately enough I live in an area where there are...

Another analyser to consider is th Youkits FG01, I believe there's a company in Canada that supplies them, a couple of people this side of the pond have bought them and get some very good results with them, I'm considering buying one as part of my portable kit due to it's diminutive size, it...

:blushing: :whistle:

As previously mentioned, it wasn't my coax and I didn't measure it, the discussion took place in cyberspace, just like this one ;) As for the 1/2WL section I know this and discuss this in another thread, but would you want to use the coax, given that it was copper plated steel and producing...

Thanks for playing along chaps, once again thanks to Steve Hunt, G3TXQ, for posing the original question. The best VSWR is 1.0:1 The worst case VSWR is 1.9:1 Here's the calculation for the worst case scenario: The impedance at the end of the first is 52*52/50 = 54.1 Ohms That's then...

I understand how a coax gets it characteristic impedance and as I didn't buy the cheap rubbish I couldn't tell you what it's impedance was, the fact it was copper plaed steel was an indicator as to why it was so cheap, the fact it was almost impossible to get a reasonable VSWR with it in line...

I'm not sure about ebay in the US, but for the absolute worst kind of cable, this is where I'd expect to find it in the UK, one chap on another forum found a VERY cheap roll of RG58 and posted it on the forum, a good few members bought the coax and all had the same experience, almost impossible...