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Hi Fausto
Well, for a long time the minimal
frequency shift in wspr was a mystery as to
how exactly it extracted data when the
Doppler spread was many times the shift on hf and
as to why time and a list of call signs was
so important, when all the other data modes ,
synchronised from the recovered signal . VW
emission software uses similar concepts
Yes your right , correlation , deep search ,
Dynamic , Ooop's , Call it what you like,
'has' to know what is in the noise , so
it can look for the pattern. Dynamic is provided
in the Opera system , 'only' for the
477 and 136 bands only , as a second
pass , low level detector, set at ~ -5 / - 6 dB
lower .
As the name implies , the system is dynamically
engaged , and the out put from the two systems
are segregated , one being the Opera data decode ,
with frequency , s/n and % fade . the other is
stamped , 'Deep search' with s/n and frequency. however , as
you note , other systems , fail to make the
distinction , or provide a solution to the problem. [ is
it a problem ?VW sold may cars ]
As Opera is not time locked , has no need
, the start times of Tx stations are
'random' so the simple solution to
test if a dynamic detection is real or false
, is compare the RX time stamp.
By elapse time from a Opera decode +
frequency
By compare to other Dynamic detections + frequency
Manually from TX beacon ,
The issue remains unaddressed in the
other systems , compared to the random pixilated out
put from the traditional 'QRSS' 'part' call
sign guessing game , Dynamic provides a robust
reliable inaction of low s/n detection and is
listed in ADIF .
The system will work with U3/PIC keyed
TX and RX linked to stand alone PC , to achieve
the full range of features , when using the
Dynamic low s/n spots , at the very least the Rx PC
needs to be linked to the WWW , to both upload
your local spot , so others are able to use
the time stamp and receive the output from
your own and other users via the 'system' ,
with the '??' check or not ....
Its true, the beacon will plot the path
between two stations , but for most of the
477/136 stations the s/n levels are so low,
its not possible to 'hear' the other
for a live qso , opportunities exist
for 477 , but 136 levels are generally well
below normal CW or data mode's, I worked V01NA
from GB4FPR with 60 watts in live CW on 502 k ,
but may be the 750 ft long wire over the sea
helped , : )
This was from the home qth , with 40 x 60 ft inv
L and 250 watts - possibly 20 dB short
of CW qso level ..
May be Luis can get JRos to put
the data mode back in the ROS package
73-Graham
G0NBD
Sent: Saturday, November 14, 2015 9:57 AM
Subject: Re: LF: RE: Re: FR5ZX on MF WSPR
Hi Graham and all,
I do not know if it is possible and I do not know
if Opera use the same decoding sistem of JT65 but
for you it is possible that a ham receive some qsl
card for 144 MHz EME qso in JT65 when in
his life
he never made a QSO via EME in 144 MHz.
Permit me some
doubt about these "deep search" systems.
It
seems very similar to those that
make QSOs with callbbok.
As you can see I do not like the digital modes because I want to be a fun to make a QSO and not
my computer.
A digital QSO is a little
how to send an SMS to
a pretty girl instead of taking her out to dinner.
Ok for the
importance of automated
systems for understanding
the propagation but when it
is determined
that for a
direction it is possible a
QSO with traditional systems why do not make a real QSO?
Every day
when I read the email I see dozens
and dozens of WSPR reports, dozens and dozens
of OPERA reports...
I rarely
see a report of a real QSO,dozens and dozens of computers that
work all night while operators are
sleeping.
Maybe I'm a purist as says Luis but
honestly the satisfaction of a CW QSO made by me and my key between the
fingers,
although I am a average operator, is unmatched.
Maybe I'll never
make a MF QSO with the US or Australia but I
think that if on the other
side there is a well-equipped
station is
not impossible.
Take the example of EA5DOM, yesterday for the first time used the CW on
630m, does not seem
to have had many
difficulties to make QSOs
at distances similar to the WSPR reports that has received so far.
Please
forgive me, but this morning I woke
up so ...
73, Fausto IK4NMF
----- Original Message -----
Sent: Friday, November 13, 2015 7:48
PM
Subject: Re: LF: RE: Re: FR5ZX on MF
WSPR
''Not considered "real" decodes by the purists
and so, garbaje qualifyed''
So the belief structure
is .
''Its possible for two
stations to randomly detect the same
station call sign at exactly the
same time''
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