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Yes that modulation schema seems to be prone to
'Gray noise' as are the envelope restoration
liner's , -30/-35 dB s/n , its not 'psk'.. a sort
of return to zero.. so is not as efficient
and as you can see creeps a little outwards ,
phase-continuous , like wspr and other modes gives a better
profile and lower s/n ... not sure as to why mfsk
was not used , but at the time ros-mf was finished
, if you change the modulator to mfsk , then
that coding structure is very similar . JR using
a hard lock at the start and a fly-wheel sync after
that .... gives more dB's for data , but at
the expense 'casual intercept' but once
locked there is a afc routine that takes care
of drift .. so may be a more practical system ?
Not yet found how to set the beacon text in
multi-psk , was going to run it later , but
at the moment ,. the best I can see is
de g0nbd k . not a lot of use for a comparative
test
G..
Sent: Saturday, March 02, 2013 5:41 PM
Subject: Re: LF: rtty 478 ?
On 02/03/2013 15:48, Graham wrote:
That would make the nose b/w zero , bit of
a 'gray' area that : ) :-) . I didn't write the spec. this is
the spectrum of the 200Hz B/W version http://www.qsl.net/zl1bpu/CMSK/ITU125.gif
Ed
Sent: Saturday, March 02, 2013 2:24 PM
Subject: Re: LF: rtty 478 ?
You are missing a Zero G, -30dB
Take a look here http://www.qsl.net/g6avk/ I will paint you some
lines at 475.210KHz
Ed
On 02/03/2013 13:39, Graham wrote:
Is that at the - 3dB points ?
Sent: Saturday, March 02, 2013 1:33 PM
Subject: Re: LF: rtty 478 ?
12.5 Hz is WIDE.?
Ed
On 02/03/2013 13:28,
Graham wrote:
Taking a walk on the wide side Ed ?
G..
Sent: Saturday, March 02, 2013 12:39 PM
Subject: Re: LF: rtty 478 ?
What about CMSK8, currently testing on 475.210, its not
crowded there but may move up later to 478.100.
Slightly Critical
tuning takes operator skill should suit Mal.
Ed
On
01/03/2013 21:28, Graham wrote:
Stereo
Multi psk has 85 hz shift amtor
- that was not there in the good old
days ?
that should work well ?
G.
Sent: Friday, March 01, 2013 9:22 PM
Subject: Re: LF: rtty 478 ?
Hi Graham, LF,
Just testing tonight for some serious RTTY
QSO attempts over weekend.
Thanks for your report & Well Done over
2 paths.
73,
Gary - G4WGT.
----- Original Message -----
Sent: Friday, March 01, 2013 9:06
PM
Subject: Re: LF: rtty 478 ?
Via Tween WEB SDR
AJCSV UYRYRY RYRSRYRY TESTING DE G4WGT G4WGT - T83QO
-KENWOOD TS-440S "RACAL LINEAR AMPLIFIER - UPM CAL ANLENET- 100OW ERP
8 RTTYREPLIEE AND E-MAIL REPORTS ARE WELCOME DE
G4WGT K AK
Sent: Friday, March 01, 2013 8:58 PM
Subject: Re: LF: rtty 478 ?
478.2 mid tones 75
shift 45.45 baud
&)--"GQU"?96 TESTING DE G4WGT G4WGT - IO83QO -KENWOOD TS-440S
" RACAL LINEAR AMPLIFIER - 12M VERTICAL ANTENNA - 100MW ERP - RTTY
REPLIES AND E-MAIL REPORTS ARE WELCOME DE G4WGT K
Sent: Friday, March 01, 2013 8:50 PM
Subject: LF: rtty 478 ?
rtty on 478 -- who ?
G.
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