Hi Markus
No Mal, Markus said its his Guess not the Answer :-)
Of course Marcus the figures stack up so I have to agree, in fact
practice agrees at this very moment as I stare at my monitor
displaying the "Challenge".
Clearly there are other factors at work to explain my practical
experience of ZERO reports of my QRS3 signal over a period of YEARS
on 10m, yet multiple world wide reports of my WSPR (when the
conditions are right of course) and all the rig has done is QSY and
changed mode. We can rule out this being a frequency phenomena too
as I have changed the QRS from above WSPR to below..
One of those factors is the human interface, Mal himself said the
other day that he has seen carriers come and go on the band but
couldn't be bothered to check them out.
Then there is the operator who can't be bothered to send a report,
with WSPR and OPERA he has no choice, other than to hide away from
the truth with no internet connection..
The need for human presence with QRS is alleviated by full time
grabbers so we can't fully blame the 'I was in bed when conditions
were right syndrome'.
As for the Answer lets give it a go, a "Challenge" is running, if
anyone notices anything different please don't post it publicly
although I will welcome reports direct.
BTW QRS3 carries about the same Data as is possible in OP4 in about
the same time, variable depending upon the actual Morse characters,
it could be longer maybe for Y0YQQ which OPERA could do in the usual
period.
73 Eddie
On 30/01/2012 11:59, Markus Vester wrote:
Eddie,
my guess is that in the "Opera vs QRSS" challenge, Mal's
odds wouldn't be bad at all:
Graham stated that Opera-8 should decode above SNR -32 dB
in 2.5 kHz (average). Referenced to 1 Hz, this is +2
dBHz average, or about + 5 dBHz for the CW carrier.
QRSS-10 could transmit a callsign approximately in the same
amout of time. It is received eg. in Argo at 0.084 Hz FFT
bandwidth, equivalent to 0.13 Hz or -9 dBHz noise
bandwidth. Thus the marginal Opera signal would be a very
comfortable 14 dB SNR in QRSS.
We typically give "O" reports on QRSS signals above 10 dB
SNR. This would mean that QRSS could be twice as fast as
Opera...
Some may prefer the digital decoder from the visual one
because "100% all-or-nothing". In my opinion this is not a
benefit, as there is no way to detect a signal below the
threshold, and judge how much was missing or what type of QRM
was present. Of course, with a digital mode yu don't have to
bother investigating spectrograms - well, borrowing a
term once coined by G3KEV, then that's the ultimate "lazy
man's CW" ;-)
Best 73,
Markus (DF6NM)
...
OP31 expected round -38 dB s/n (ave) OP8 ~ -32
dB
G..
-----Ursprüngliche Mitteilung-----
Von: qrss <[email protected]>
An: rsgb_lf_group <[email protected]>
Verschickt: So, 29 Jan 2012 9:25 pm
Betreff: Re: LF: 500 opera V
So
Mal
Can you see or hear my 12WPM Morse ident between my OPERA
signals? I doubt it. I could put QRS3 between, that would be
a good test. Say a cryptic message for decipher, one
transmission and that is it, if Opera decodes and the QRS
remains unread OPERA wins.
Eddie
On 29/01/2012 19:53, Graham wrote:
R Mal
Those signals where about 10 db
over the limit , so will show , OP16 , is
about 6 dB lower again. but a decode is a
decode.. good start.
14:44 500 G3ZJO de G3KEV Op4 142 miles -22 dB in
SCARBOROUGH
136 is being most used at
the moment RA9CUA is monitoring
G..
Sent: Sunday, January 29, 2012 6:14 PM
Subject: LF: 500 opera V
MF
On 500 Khz so far signals decoded
in Opera mode have been visible on the waterfall
therefore had the mode been QRSS the result would have
probably been better and quicker in QRS 3 - 10
The mode is however interesting
and needs little operator intervention.
de mal/g3kev
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