Message-ID: <13ccf2e8112.marcocadeddu@tin.it>
Date: Tue, 12 Feb 2013 17:13:16 +0100 (CET)
From: "marcocadeddu@tin.it" <marcocadeddu@tin.it>
To:  <rsgb_lf_group@blacksheep.org>
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Subject: R: Re: LF: Was  Considerations about wide DX experiments - how slow
 should we go?
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Hi Alan,
of course we are all joking and support Stefan hoping that new=20
positive datas can give more thoughts!
By the way I'm still struggling sometime because I'm not able=20
to leave a trace on the TF grabber although at the same distance was=20
able to leave nice signals on the Haifa grabber... (no chance to have=20
again active it?)

so...go Stefan go! GL

73, Marco IK1HSS
----Messaggio originale----
Da: alan.melia@btinternet.com
Data: 12-feb-2013 15.42
A: <rsgb_lf_group@blacksheep.org>
Ogg: Re: LF: Was  Considerations about wide DX experiments - how slow=20
should we go?

Hi Marco a case of "never mind the theory, show me the data " :-))
Jay's plot shows what I was thinking about quite well. Markus's signal=20
is=20
weaker and suffers fade decode problems, but Stefan's signal is=20
stronger and=20
shows no fading. I think this is due to the "non-linearity" of the=20
waterfall=20
display. From experience of my use it only takes a change in strength=20
of=20
about 3dB to go from "M" to "dogbones". Thus my idea that the fading=20
at=20
distance is much shallower.....it doesnt make it any less difficult to=20
decypher, but you may only need another dB or so for fully readable=20
once you=20
display on the trace.
You can lay off time against improved readability by as somone asked=20
"stacking" modes, like Wolf used to do. This it does need accurate=20
timing,=20
and is akin to how amateur astronomers produce such spectacular=20
pictures=20
with backyard telescopes. CW ops do it as well(!!) ....you know "ur 599=20
pse=20
rpt all" :-))

Alan
G3NYK

----- Original Message -----=20
From: <marcocadeddu@tin.it>
To: <rsgb_lf_group@blacksheep.org>
Sent: Tuesday, February 12, 2013 1:30 PM
Subject: R: LF: Was Considerations about wide DX experiments - how=20
slow=20
should we go?


On the theory hornets cannot fly..
Let's dream again Stefan!
73, Marco IK1HSS

----Messaggio originale----
Da: hellozerohellozero@hotmail.com
Data: 12-feb-2013 4.27
A: "rsgb_lf_group@blacksheep.org"<rsgb_lf_group@blacksheep.org>
Ogg: LF: Was  Considerations about wide DX experiments - how slow
should we go?


I would agree Alan that on the longer hauls I still see a more rapid
fade pattern but not the couple of mins typical of the shorter hop
stuff - - I sort of got used to "20 mins" for 137Khz on the Transpolar
and Trans Siberian paths into China from Eu, but it was a little more
than "5 mins" at 500Khz - that sort of aligns on what I saw at sea on
the Antarctic/South Atlantic paths on 500 back to Portishead path back
long long ago, and what I have heard from here and Fiji into Oz and NZ
- but I also recall the fades became more vertical and shorter during
the more disturbed periods - again this way very dependant on the path
profile and where it and what it crossed on the Rhum line geomag and
whether it was North/South East West - again cutting across the "lines"
was far more problematic.   I still scratch my head to see the MUF map
of the world and how it looks more like a complicated barometric
pressure map with depressions and High pressure areas :-)  What I would
do is not to discount the long periods out of hand at 500 - I have a
tingly feeling that dot 30 is as slow as I would go but Ive been proved
wrong countless times :-) What I do know is to date that bar Japan to
Alaska (apart from Canada/USA) no signals have reached the levels that
my old CW ears could decode, and truthfully I dont think they would
ever get to that level at our ERP levels and lack of the salty stuff.
Mind you I would love to set up an MF station here on Maui - Ive
already picked my spot and the tower I would steal (Junction of
Lahaina/Kihei road at South Kihei).  Im trying to twist a certain arm
to install MF on our expedition ship, but we dont have a lot of space
for the normal type of array Im used to. We will see Laurence KL
1X/KH62AZT
 > From: alan.melia@btinternet.com
> To: rsgb_lf_group@blacksheep.org
> Date: Tue, 12 Feb 2013 01:09:31 +0000
> Subject: LF: Re: Considerations about wide DX experiments on 630m and
tonites QRSS-60
>
> Hi Stefan I think that maybe the right approach. I think you may find
that
> the "perceived wisdom" on fading rate v QRSS speed is based on
relatively
> short paths. I suspect it may well be very different at real DX
range, that
> is several hops.......>6000km. There obviously is some sort of a
problem
> because the wavelength is much shorter than 136kHz so the phase
changes more
> rapidly with ionisation and "apparent refection height" but you need
two
> "modes" of nearly equal strength to get extinction. This may not be
so
> prevalent at long ranges on 470kHz. The experiment will be very
interesting
> if you can start to leave traces on distant grabbers.
>
> Alan
> G3NYK
> ----- Original Message -----=20
> From: "Stefan Sch=C3=A4fer" <Stefan.Schaefer@iup.uni-heidelberg.de>
> To: <rsgb_lf_group@blacksheep.org>; "Vasily Savchenko" <ua0snv@yahoo.
com>;
> "Garry and Linda Hess" <k3siw@sbcglobal.net>; "Douglas D. Williams"
> <kb4oer@gmail.com>; "Andy - KU4XR" <ku4xr@yahoo.com>; "Edgar J
Twining"
> <edgarjtwining@virginbroadband.com.au>
> Sent: Monday, February 11, 2013 10:57 PM
> Subject: LF: Considerations about wide DX experiments on 630m and
tonites
> QRSS-60
>
>
> > MF !!!!!!!!!!!!!!!!!!!!!!! ;-)
> >
> > Edgar in Tasmania was recently asking if i have some plans about
DX
> > experiments on 630m. Well that is a path of > 16000 km. However we
do not
> > have real experience if that is easier than 2200m or rather
impossible.
> >
> > At least i know that there was not even a single decode by UA0SNV
in my MF
> > WSPR and QRSS tests so far, while it is no problem on LF (OK my MF
signal
> > is weaker than my LF signal). Thus i would guess that it is much
harder to
> > get some traces of a signal on 630m. We will try anyway!
> >
> > I'm starting to run a QRSS-60 transmission on 476.172 kHz (+- a few
Hz)
> > for the night. Maybe someone across the pond will catch something.
We, or
> > at least i still have no experience about the QSB problem on very
slow
> > QRSS transmissions on MF. It would be interesting to see a
spectrogram.
> >
> > On air in a few minutes.
> >
> > 73, Stefan/DK7FC
> >
> > PS: No, not only beacon transmissions, i've just had a > 1 hour
long CW
> > QSO with PA0LCE and DK6SX/p! Also contacts to OK2BVG and S57A.
> >
>
>