Re: LF: MF 630m: False Decode or Real?

["Graham" <g8fzk@g8fzk.fsnet.co.uk>]

Yes I agree  very well  sad , can talk the talk, but  would  appears to  have problems   walking  the  walk .

 

It   actually  bears no  resemblance  to  how the  system  work's or shows insight  to  the  difference between a correlation  system   and  a  data  transmission  system

 

Im not quite  sure  , how  a  correlation  process  is  supposed to  identify  a  'bit'  of  data or  decode  anything  as  it  matches  patterns  and has  nothing  to  do  with  the encoding   and  decoding  of  data  and is  purely a  time  based   system

 

But gives  perhaps,   a  insight into the  working  of  other  popular  systems , which may , then  not  be  quite  as  intelligent as  made out to  be ? the  web was full  of comments  round  the  need  for  a  call  list  in a   data  mode  ...  correlation is not  limited to a  single  on/off  carrier , non   spread  spectrum  mfsk  systems  may also  be  so  inspected .only  needs  the  coding  template  and  expected  call  list . but thats  another  story

 

As for the qso  definition , what  ever ,  other  non  plain text  systems  , also  fall into  the  same  category .

 

The main thing is  its free  and  complies with the  part-97  bandwidth  expectations   

 

73-G,

 

 

From: Rik Strobbe

Sent: Thursday, May 21, 2015 7:47 AM

To: rsgb_lf_group@blacksheep.org

Subject: RE: LF: MF 630m: False Decode or Real?

Hello Wolf,

 

well said.

From the IARU R1 VHF managers handbook:

 

A valid contact is one where both operators have copied both callsigns, the report and an unambiguous confirmation. However no recourse should be made during the contact to obtain the required information, change of frequency, antenna direction, etc. via other methods such as the Internet, DX Cluster, talk-back on another band, telephone etc.

 

Similar statements are found in other documents such as contest and award rules.

 

73, Rik  ON7YD - OR7T

 

---

Van: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.org] namens wolf_dl4yhf [dl4yhf@freenet.de]
Verzonden: woensdag 20 mei 2015 22:40
Aan: rsgb_lf_group@blacksheep.org
Onderwerp: Re: LF: MF 630m: False Decode or Real?

Hi Jochen,

I think the discussion about Opera's own 'deep search' mode (or whatever
the proper name is) was done here (or on "the other" reflector) over a 
year ago, and the main problem I see is that the 'real time web-based
exchange' of currently active stations means fooling oneself.
Consider this: You know there are only four possible callsigns which
have been transmitting, so in reality the software only has to decide 
for a TWO BIT number. Much easier than "really" decoding the entire 
number of message bits in an Opera message.

In my very personal point of view, this 'real time web exchange of
stations (calls) which are currently transmitting' should not be used at
all.
For comparison, Markus' (DF6NM's) own deep search uses a quite large 
table which is *static*, which means that his decoder has no chance to 
play unfair (because it doesn't know who's currently active or not), and 
it also doesn't know what others receive (over the internet). What I 
don't know is how many stations are currently in that list, and thus how 
many bits the algorithm effectively has to "decode" (well, it doesn't 
really decode, it also makes a best guess from a limited number of list 
entries to chose from).

All the additional data which look as if they were "decoded" (eg "VK3ELV
... 140w + Top loaded L 18m vert 80m horz") have been taken from a
database (***including the callsign***), not radio .. the only real 
information  is the '- 37 dB' report, and the two question marks which 
imho may as well have been ten or twenty (considering the season and the
distance).

Well just my two pence of wisdom. I don't use Opera and don't think I
ever will.

Cheers,
   Wolf .










Am 20.05.2015 22:03, schrieb J. Althoff:
> Hi Wolf,
>
> You are not disappointing me at all. I put this issue under discussion myself.
>
> Please share your opinion about this to this topic to us in detail. Maybe I missed
> A discussion about this before, but I am very interested in arguments about this
> Topic.
>
> Thanks, Jochen
>
>
>     -= DF1VB =-
>    -= KH2MM =-
>   Jochen Althoff
>   df1vb@gmx.de
> +491712020206
>
>
>> Am 20.05.2015 um 21:44 schrieb wolf_dl4yhf <dl4yhf@freenet.de>:
>>
>> Sorry to dissapoint you but .. no, no, no, and again, no.
>>
>> 73,
>>   Wolf
>>
>> Am 20.05.2015 20:02, schrieb Jochen Althoff:
>>> Just popped up at my RX:
>>>
>>> 17:52    477 VK3ELV de DF1VB/3 Op8 Deep Search ?? 16348 km -37 dB in Dortmund with 140w + Top loaded L 18m vert 80m horz
>>>
>>> Any comments welcome
>>>
>>> 73, Jochen
>>
>
>