Message-ID: <AC666FAFFAF340258B396B3B6D0949A6@AGB>
From: "Graham" <g8fzk@g8fzk.fsnet.co.uk>
To: <rsgb_lf_group@blacksheep.org>
Date: Sat, 23 May 2015 15:46:37 +0100
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Subject: LF: MF 630m: False Decode or Real?
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Status: O

 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" <g3zjo@psk31.plus.com>
Sent: Saturday, May 23, 2015 11:14 AM
To: <rsgb_lf_group@blacksheep.org>
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