Hi Roelof thanks for your observations. It is great to get information from
different frequencies and different paths. I looked at NDBs but could not
think of a reliable way of automatically monitoring signals. I was worried
about the shared frequency problem.....knowing what I was listening to. I
started monitoring CFH on 137khz when it was on continuously. when it went
off. I transfered to trying SXV but could not make sense of it. Brian
Rogerson CT1DRP took up the challenge and collected signal from DCF39 24/7
for about 4 years.
What might be interesting if you could classify the path length of different
paths (It depends whether you can find sufficient at the right range) It
would be interesting to try and correlate the excess path loss against "hop
number". I feel that if 1 hop has 6dB excess attenuation, a 3 hop path
(5000 to 6000 km) should show around 18dB
An interesting aside I spotted might be of interest to you. It regards
daytime skywave so a path of about 1200 to 1400km. I found that the
"precipitated" hot electrons from a big event were sufficient to give a kind
of prolonged "flare effect". The increased signal during a flare event is
due to he increased D-region ionisation. Similarly the increased ionisation
due to precipitation can enhance the daytime skywave signals. The reports I
have seen suggest the signals are most clearly enhanced around mid day at
mid path. The effect is often only present for about one or at most two
days after an event.
Great stuff this LF :-))
Alan
G3NYK
----- Original Message -----
From: "Roelof Bakker" <[email protected]>
To: <[email protected]>
Sent: Tuesday, July 17, 2012 8:43 PM
Subject: Re: LF: Re: Kyoto Dst question
Hello Alan,
Thank you very much indeed for your explanation.
I have now a more clear picture what is going on and your findings agree
with my own observations.
My location is excellent for reception of Canadian NDB's and I have been
monitoring them for 4 years now.
I use a PERSEUS SDR which is recording 200 - 600 kHz every night.
This summer the path to New Foundland has been open almost every night.
Until the latests solar event, accompanied with a major drop in the Kyoto
Dst figures.
We will see how long it takes to recover.
Best regards,
Roelof, pa0rdt
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