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LF: MF 630m: False Decode or Real?

To: <[email protected]>
Subject: LF: MF 630m: False Decode or Real?
From: "Graham" <[email protected]>
Date: Sat, 23 May 2015 15:46:37 +0100
Importance: Normal
Reply-to: [email protected]
Sender: [email protected]
intelligent life in other Galaxy's ? Like the Bar ? 11:14 . Suns not over the yard yet .. Tad early Eddie ?
Armature radio V  Armature  hour , take 2

Opera MF and LF is a BOGOFF mode , Buy one and get one free , just that its free to uses and the first is a data mode the second mode is a correlation system , dynamically engaged .. page 70 seems to miss this rather important fact along with the design solutions embodied therein , I'm waiting for page 71 ..
The  test of a good design  is that no one  notices , it just works .

In that 24 hour window , Opera LF produced no false data detections or false dynamic detections , where as the wspr system regularly fills the LF map , a simple test of design , preventing false correlation detections is more difficult than false data . Opera LF is -40 dB and -45 dB ... that well cool as J C would (of) said

Now the  tacky bit

As Im sure Markus will tell, OPDS and Dynamic share the same design criteria To drag low signals out of noise , by pattern matching , OPDS makes use of Wolfs some what excellent spectrum software as DSP , whilst Mr. Ros uses his own designs . both systems reliably produce false detections when subjected to noise .. not all the time , just depends on the detection monkeys sense of humour on the day.
The design solutions' branch , OPDS makes accurate frequency
measurement and Bandwidth , along with allowing parameters to be
adjusted by the user ,as well as maintaining the look up table
hence ultra stable TX and RX can give advantage .. And as pointed out
, presents the user with a set of parameters, which may be used as
validation
Opera Dynamic retains the Plug and Play house style , yes these are
criteria , but are evaluated by the system , load it and it dose the
rest , Opera data runs as normal , Opera dynamic is engaged should
the decoder fail , the sever handles the validation and maintains the
list.
Both systems OPDS and DYNAMIC produce false real hits , Dynamic take
things one step on, where wspr uses the internet as part of the DSP
sync . Opera Dynamic uses the internet to pool ' recovered time' data
and validate the spots by identity and coincidence of time ..
Now mines a  pint  or  are we onto  shorts  now ?

73-G



--------------------------------------------------
From: "g3zjo" <[email protected]>
Sent: Saturday, May 23, 2015 11:14 AM
To: <[email protected]>
Subject: Re: LF: MF 630m: False Decode or Real?

Wolf / LF

Don't you know that several of us are using Opera to reveal intelligent
life in other Galaxy's, occasionally we do get a random two bit number.
We are now desperately trying to get an internet connection, then we
will know, Who they are, Where they are, What Power they are running,
The antenna used, The distance to their planet and When the message was
transmitted.

Like yourself because of the internet information exchanged, even prior
to deep search, I lost interest in the the mode for Amateur Radio.
But its great for comedy, like part quoting a statement in RadComm
proves that WSPR produces false decodes which makes Opera legit. I don't
know of any case of WSPR producing a false decode with a valid Callsign,
Locator, Power and Time.
Quoting the rest of the paragraph makes it clear, ## such false (WSPR)
decodes are rare but they do happen. They can always be spotted: false
hits as the callsign (even if it has a valid prefix) is unlikely to
agree with the locator information field.##

Admittedly WSPR was ill conceived, it needs to have 5 data units not 4
to remove the need to use two transmissions to send commonly needed /P
etc. but its good and we are stuck with it until the next major
development comes along.

Opera has made a fool of too many vulnerable operators.

73
Eddie G3ZJO

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