carefully levelled steel track
Its funny you mention that ,
as it occurred to me , using one tone as a
frequency marker was a bit like a mono rail , but each
to his own , as is demonstrated by JR , gps
/time/coherency are not necessary to achieve quite
acceptable performance , may be 'we' can
persuade dfc31 little brother , to
send a ros-mf-2 data mode beacon one
night , that's the same s/n as wspr , but
is a normal type what you want data mode :
)
Wobbly bob is a organic anti coherent
compound that is only available in
imperial measures and may be used to
induce instability in carbon based analogue systems ,
analogous with Doppler spread and
multi path reception
Dragon, That's interesting as I believe
the export of German Silver to China
was one of the high value luxury goods that was
part of the reciprocal trade at the end of
the dynasty , with plates etc the other way ,
assume that's where the lucky Dragon and Kite made
its way back ,
G.. ))
Sent: Thursday, November 29, 2012 10:59 PM
Subject: Re: LF: WSJT-X v0.5 r2786_JT9-10
Hi Graham,
of course I would seriously compare modes,
based on conveyed bits per transmitted energy, or available radiated
power. Of course I'd NEVER EVER dare to compare anything against
handmade CW, would I ;-))
Won't delve into the numbers
again. Well you say Opera may be slower but is more
robust... Then it's like the farm tractor which can master rumbly
ground, while 'JT is the fast train running only on a
carefully leveled steel track? ;-) On the other hand I believe there is a
lot more potential in the Opera modulation scheme, if only it were be
transmitted and received coherently.
However looking at my
spectrogram with Stefan booming in here, I have to say I'm glad he's currently
not using on-off-keying...
But after all we're not on
a crusade, hence the smileys ;-)
Best 73,
Markus (DF6NM)
PS what is "wobbly
bob"?
PPS There's also a German dragon
which brings luck to those using it. We use the same word
"Drachen" for dragon and kite ;-)
Sent: Thursday, November 29, 2012 8:47 PM
Subject: Re: LF: WSJT-X v0.5 r2786_JT9-10
Mk..
Are you seriously comparing a time
locked narrow frequency tolerance
MFSK system with one based on
a free running Manchester coded OOK
system , immune from Doppler spread and capable
of simultaneous multi decodes running
on standard ham 'wobbly bob' equipment ?
Not forgetting the 'wobbly bob' system
gives a average of the signal along to the time
line and not a peak (inverted) value , so direct
comparisons are a little misleading ,
Just the same as say 'Long' means
long in English and Dragon in Mandarin and
a English dragon breaths fire and the
other one is made of fishes and brings good
luck ...
G: )
Sent: Thursday, November 29, 2012 5:24 PM
Subject: Re: LF: WSJT-X v0.5 r2786_JT9-10
Stefan,
yes, theoretically JT9-10 should work down to SNR
-37 dB in 2.5 kHz (which would read -41 dB on the Opera scale ;-)
Each of your transmissions has been
decoded here. Are you receiving JT9 as well?
Best 73,
MArkus (DF6NM)
...
