Re: ULF: EbNaut message transmitted from ground loop

[DK7FC <selberdenken@posteo.de>]

Am 07.04.2019 07:17, schrieb Paul Nicholson:
> Perhaps also the longest ground loop antenna used for
> amateur transmission?
You never know. I can imagine that a few more people used similar 
antennas, but most likely not in combination with coherent signalling 
and modern modes such as EbNaut, and with so much power and optimised 
efficiency. Some people may have done local tests (< 5 km) in CW or use 
audio (music, voice) to cross some 100m, partly with metallic 
underground infrastructure (water pipes...) to support propagation.
I bet there has not been anything beyond 20 km distance, and not at all 
something international.
An OM (OT!) of my radio club told stories of his early radio 
experiments. He had a friend in some 100m distance and they lay out a 
small hidden wire into they ground between their QTHs, using the earth 
as the back 'wire'. They communicated over that wire which is nice :-) 
But first you need someone who's interested to do something like that. 
Nowadays you may need some more wire to find the next QSO partner :-)
73, Stefan