Re: LF: JA/EU

["Douglas D. Williams" <kb4oer@gmail.com>]

Mal, I understand the relevance of what you are saying on HF, and even medium wave, but could you (or anyone who cares to) give me a brief explaination, or point me to a source of information, on LF propagation? I was under the (admittedly simplistic) understanding that, the lower one goes in frequency, the more the signal propagates via groundwave. I do know that almost all military installations transmitting in the VLF/LF bands use vertical antennas (very, very large ones with huge capacity hats). Do signals at 136 kHz experience "skip" from ionispheric reflection, similar to HF signals?

 

Doug KB4OER

On Sat, Jan 7, 2012 at 5:32 AM, mal hamilton <g3kevmal@talktalk.net> wrote:

LF

No sigs visible in JA from EU last nite at the peak time, around 2150 z. The JA grabber moved freq so not possible to check at 0740z the other peak time.

I think the antenna used for transmitting has some influence on the launch angle and distance covered and likewise the type of antenna at the receive site. ie low or high angle.

A vertical TX antenna system as high as possible would produce low angle signals, preferable for long haul DX, and low horizontal wires, loops etc would produce high angle, ideal for short ranges but not ideal for DX although the odd time high angle also does the trick. Large vertical loops fed correctly at the side  produce low angles but small vertical loops relative to frequency ie LF might be difficult to evaluate.

de g3kev