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Message-ID: <5.1.0.14.0.20021218114357.00afbe68@gemini.herts.ac.uk>
Date: Wed, 18 Dec 2002 12:27:39 +0000
To: rsgb_lf_group@blacksheep.org
From: "James Moritz" <j.r.moritz@herts.ac.uk>
In-reply-to: <1a8.de39a4a.2b319c33@aol.com>
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Subject: Re: LF: M0BMU Jason Success!
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Dear LF Group,

Very pleased that Jason has made it across the pond - thanks to W1TAG for 
the reception, and also to I2PHD, I2CZL and KK7KA for the software 
development. The actual message was "M0BMU M0BMU JASON 95 IO91VR", repeated 
endlessly. I was running 1.2kW into a 13m high inverted V, giving about 5A 
antenna current - in the past, field strength measurements put the ERP of 
this set-up at almost exactly 1W. (incidentally, in last night's frost, 
loss/ground/system resistance was down 15% on the previous night...)

G0MRF wrote: ...Not only the first Jason reception but also the first mode 
other than QRSS to cross the pond. ..
Not quite - nearly a year ago, several people copied my "7FSK" tests - 
sometimes much to their annoyance! Also, the previous year, W1TAG copied 
one of the WOLF tests - it seems John and myself currently have the 
monopoly on Transatlantic LF digital modes :-)

Regarding possible use for T/A QSOs, each character (including the spaces) 
lasts about 24 seconds in Jason - so the kind of minimal QSOs being 
discussed at the moment could be executed within 30 minutes with solid copy 
both ways. Of course, last night's conditions did not give perfect copy - 
but looking at John's screen shot, it was not actually far off doing so 
over at least 1 half hour period. I am confident under good conditions, 
Jason would be a viable 2-way transatlantic mode. A nice feature of Jason 
is that it is not too fussy about the frequency - assuming you are going 
for "blind" reception, ie. you are not adjusting the tuning in response to 
a received signal, I think about +/- 1Hz accuracy would be adequate to get 
the whole signal within the yellow lines on the Jason waterfall.

Cheers, Jim Moritz
73 de M0BMU


>one day be spanned with standard CW.
>
>How important was your ability to accurately set frequency John? Is there 
>an acceptable margin of error with Jason 95?
>
>73
>
>David   G0MRF