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Hi Doug
I see another has replied to your query which is more or
less correct but there are other variables depending on installation especially
in radio amateur circles.
Did you observe any acty on 136.173 earlier on today. I
was on TX for a short period before my sunrise 0630/0730 utc
73 es gl
de mal/g3kev
----- Original Message -----
Sent: Saturday, January 07, 2012 12:06
PM
Subject: Re: LF: JA/EU
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 <[email protected]>
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
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