Re: LF: AW: 8.97kHz - Near field and radiated signals?

[Roger Lapthorn <rogerlapthorn@gmail.com>]

Hi Jacek,

Thanks for this encouraging information. I'll definitely try an e-field TX antenna later, although space is very limited in my garden.  The grounded electrode pair "antenna" does appear to be quite effective, but I need to compare this against a TX e-field antenna and loop antenna.  I've some questions:

• What antenna did you use for RX? Loop, e-field probe?
• Have you tried TXing using grounded electrodes? If so, what range did you achieve and what RX antenna did you use?
  

Thanks again.

73s
Roger G3XBM

On 25 May 2010 22:30, Jacek Lipkowski <sq5bpf@lipkowski.org> wrote:

On Mon, 24 May 2010, Roger Lapthorn wrote:

 - The best DX targets are quite modest: I would like to exceed 1km

 initially with the TX power I currently have (around 4W). If I could reach
 G6ALB in the next village 3kms away I would be delighted. If I got any
 further I would be both amazed and VERY happy!

Roger - try an e-field antenna. for a few years i have been doing tests with loops, and the results were not that good. the best distance was about 700m in the city during wintertime with about 40W. i wish i had tried an e-field antenna earlier.

the first results with a 40m horizontal wire abt 15m up were far better. i got 1.3 km without problems using about 3W in april (so more qrm than in winter): http://acid.ch.pw.edu.pl/~sq5bpf/ham/vlf/sq5bpf_vlf_test_20100406.jpg

the matching was done via a tv transformer, which i see is getting quite popular now :)

since you're in a village area you will probably have much less qrm. 3km in the winter seems to be a realistic goal.

vy 73

Jacek / SQ5BPF

-- 
http://g3xbm-qrp.blogspot.com/
http://www.g3xbm.co.uk
http://www.youtube.com/user/g3xbm
G3XBM    GQRP 1678      ISWL G11088