On Mon, 10 May 2010, Stefan Schäfer wrote:
PS: I have built a small TX antenna at my new home QTH in Heidelberg. With a
TV transformer and my 300W PA (running at 15W DC input) i apply about 2kV rms
on a 10m horizontal wire, about 3m above gnd. The distance to the grabber
here is 1,1km. Hopefully i can see something, at least in DFCW-600...
i've tried a tv transformer with a 40m horizontal longwire and abt 3W
input. the signal can clearly be seen on a mobile receiver 1.3km away from
the antenna:
http://acid.ch.pw.edu.pl/~sq5bpf/ham/vlf/sq5bpf_vlf_test_20100406.jpg
so you will surely receive it with a better rx (the receiver here is a
crude bf245 active antenna + lowpass). since then i've improved the
distance by some 300m.
i didn't post it to the list, because i hoped to optimize the setup, hope
to be able to run higher power.
VY 73
Jacek / SQ5BPF
|