Message-ID: <3C5010A1.FA2F482C@att.net>
Date: Thu, 24 Jan 2002 13:48:17 +0000
From: "Dexter McIntyre W4DEX" <dmcintyre@att.net>
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To: rsgb_lf_group@blacksheep.org
Subject: Re: LF: Re: Jason Tests
References: <5.1.0.14.0.20020123175959.00ac4190@gemini.herts.ac.uk> <5.1.0.14.0.20020124114059.00a7a518@gemini.herts.ac.uk>
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James Moritz wrote:
> 
> BTW, does anyone know how to compare the weak signal performance of Jason
> and QRSS or DFCW? It seems clear that the increased bandwidth must result
> in some loss of SNR, but there will also be gains because the data is being
> transmitted faster for a given dot length.
> 
>

Jim,

I did look for your 135.990 transmission last night.  I saw nothing but
didn't expect to.  There were heavy thunderstorms in the mid US and
another small group to my SE wiped out LF reception for me.

Lyle, KØLR, made some test comparing JASON with other modes.  Here is
his initial results:

>>>>>>>>>>
I was
trying to compare Jason and WOLF, using the same old noise recording
that
was the "standard" for comparisons of other weak-signal modes a while
back.
In those tests, 12 WPM CW was good down to about -18 dB and QRSS3 was
good
maybe to -27 dB. In today's tests, WOLF produced solid copy after 288
seconds at -35 dB. Jason seemed to be erratic at any signal level, so I
knew
something was wrong with my receiving setup. Turns out that my Pentium
233
MHz "ham" computer requires the slow mode setting (Jason won't run on my
900
MHz Pentium III). After switching to slow mode, it looked like Jason is
farily solid down to -30 dB, and gives partial copy at -33 dB. Results
could
be completely different under other combinations of QRN and QRM. Anyway,
with the right settings I might have had better results on your Jason
signal.
>>>>>>>>>>

73,
Dexter