Over recent weeks, I have run literally hundreds of thousands of NEC models of small transmitting loops (STL) over real ground. The objective was to try to discover some simple methods for initial design of a STL, particularly an estimate of ground loss of STL mounted near natural ground. Continue reading A method for initial ground loss estimates for an STL
There seems a never ending stream of low end antenna analysers appearing.
The Mini60 antenna analyser is one in that vein, and is sure to prove popular because of its low price. As is common, there does not appear to be an English language user manual and the specifications in eBay ads are not very reliable (eg weight: 200kg).
This article has been copied by request from my VK1OD.net web site which is no longer online. The article may contain links to articles on that site and which are no longer available.
(Tester 2013) described a coaxial collinear array for VHF/UHF. Tester describes the antenna a collinear is a vertical antenna whose resonant elements are connected along a common line (ie co-linear) so that each element is opposite in phase to its neighbour.
He is a little confused, in fact, the elements are in-phase with each other so that in the horizontal direction, the contribution of the current in each element to the far field is an additive or reinforcing one.
He goes on to say [i]f you are not into antennas, that mouthful is, fortunately, very easy to achieve... but is it?
I left it for readers to visually form a view of the difference between the antennas, and the implications for credibility of folk lore about the two antenna types, this article addresses the quantitative difference between the average S/N ratio of the antennas.
This article compares a series of models of a small transmitting loop at varying height above real ground using NEC-4 and NEC-2.
The models are of an octagonal loop of thin wire of the same area as a 1m diameter circle over real ground (0.007/17). Height is measured to the centre of the loop, and all impedances are wrt the main loop.