[Premium-Rx] The 'Ideal' Logwire

[NewRadioChap at aol.com]

Does anyone know if there is an 'equivalent' circuit (or lab set-up) that 
will simulate a typical logwire (single-ended) antenna working into a co-ax? 
I don't just mean the theory - I am looking for practical work.
I have been doing experiments and research on broadband balun designs and 
construction - particularly VLF and HF (approx 10KHz to 10MHz) to optimise my 
receive capability using a variety of longwires from 20ft to 200ft. I've 
found that most commercially made broadband balun transformers for receive do 
not appear to work very well - if at all - and have no benefit. My homebuilt 
ones don't fair any better. When frequency swept, all exhibit distinct 
bandwidth/resonant peculiarities. In fact, by incorrectly connecting certain 
types of balun, I get a voltage boost (gain) at LF, with high loses at HF! 
This is confirmed on the antenna sweep. There must a pile of work previously 
carried out on this that someone can point me to, I'd much appreciate it. If 
I can find a simulation, it will save me putting life at risk trying to do 
measurements up a 40ft tree, and instead do them indoors! Every dB counts....



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