Jim
The variations in signal you observed was due to the Balloon being buffeted
about due to wind, thermal dynamics, and up drafts and not a valid
propagation study. I was in touch with Ossi and he described to me that the
baloon was almost horizontal at times, therefore the wire antenna attached
would vary from vertical, slant, horizontal.
He also said that the antenna current was well down at times, so many
variables effecting the transmitted signal. All the facts have to be
gathered before a valid observation is made otherwise its all Guesswork and
supposition.
To do a meaningful propagation study the transmitted signal needs to be
launched from a FIXED antenna.
The same criteria applies to Kite borne antennas.
mal/g3kev
----- Original Message -----
From: "James Moritz" <[email protected]>
To: <[email protected]>
Sent: Monday, February 07, 2011 11:09 PM
Subject: LF: Re: OE5ODL over different paths
> Dear Ossi, Markus, LF Group,
>
> I was quite interested to notice the sharp dip in OE5ODL's signal at
around
> 1430utc today, and in light of Markus' comments, I used the cursor
> facilities in SpecLab to manually read off the signal levels, avoiding the
> noise bursts. I also did a quick field strength calibration of the
> loop/receiver - the resulting plot of field strength vs time is shown in
the
> attachment (the vertical axis should say "dBuV/m"). As well as the deep
null
> around 1430, the signal level seems to rise several dB during the day,
> peaking around 1800 - 2000, and now starting to fall off. Also, a
downwards
> drift in frequency of about 1.5mHz can be seen.
>
> Cheers, Jim Moritz
> 73 de M0BMU
>
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