Re: R: Re: Fwd: Re: LF: VK1OD's analysis of the MiniWhip antenna

[Stefan Schäfer <Stefan.Schaefer@iup.uni-heidelberg.de>]

Well, i find it not strange at all that it works. The discussed antennas 
are just impedance converters. The input impedance is in the range of 1 
MOhm and the output impdeance is lower.
Did you never see a (small) voltage on an oscilloscope when a simple 
probe is connected, while transmitting on LF/MF? The scope has an input 
impedance of 1 MOhm (and some pF). Now take an oscilloscope with battery 
supply, connect the probe and put it into a Helium balloon and let the 
probe hang down. Then let the stuff rise to near your TX antenna and see 
the signal on the scope. It would also work without a ground!
(Then see all the stuff crashing down in your neighbours swimming pool).

Compared to the scope, the discussed antennas just have to be more 
sensitive, minimizing all that noise stuff, while my scope starts at 
5mV/div. And 1 mV signal level would be a BIG signal for the RX! :-)
73, Stefan/DK7FC