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LF: OPERA The new CW / QRSS replacement data mode

To: <[email protected]>
Subject: LF: OPERA The new CW / QRSS replacement data mode
From: "Graham" <[email protected]>
Date: Mon, 2 Jan 2012 00:08:04 -0000
Importance: Normal
Reply-to: [email protected]
Sender: [email protected]
All,

 

After  some  time  in development  the  136/500  version  of the  Opera  data  mode  is  ready  for  experimental  use .

 

Download  links  are  available  from  myself  or  Gary, G4WGT  as the  versions  may  change  , these  may  also  change  ,

 

Users  are  invited  to  join the  Opera  yahoo   group  http://groups.yahoo.com/group/O_P_E_R_A_/?yguid=131323118

 

At the  moment , spots  are  distributed to  other  OP users  on line  at the time ,. future intent  is to  link   to  the  PSK-Reporting  network and  for  a  HF version  and  possible  limited  QSO  mode , allowing  under  the  noise  qso's  with  a simple  xtal  tx

 

There  is a  on line  chat  mode to  facilitate  tests  etc

 

The  software  is  available  for  all  , free  to  use  ,

 

Happy  new year  to  all  and  good  luck

 

73-G ..

 

 

 

 

 

 

OPERA  The  new  CW/ QRSS  replacement   data mode

 

There  is  always the  assumption that  all   armature  radio  stations  can  effectively   translate  what  ever  new  soundcard  data  mode  that  is  coded to  radio  frequency..

 

The  question  I posed was  ?What  about  those  who  cannot , and  only  have  CW transmission  facility?s?? ?

 

Never did get a reply

 

So  after a  long  exchange  of emails , the  concept  of  a  serial  data  mode that  used only  one  tone  , on/off  keyed , with a  eye  on the  qrss  system,  was  finally  discussed  and  coding  work  begun, an  initial  statement  that in software , could  be  achieved  a lower  level  of  detection  than that  required to  produce a  line  on a  spectrum  plot set the  scene for  a  what  was  originally  proposed to  be a  simple  data  mode, turned into to  a  race to the  noise  floor.   

 

 

OPERA

 

Is  a totally   new   Data  / Beacon  mode ,  profiled  for the  136  and  500  bands  , with  HF  possibility?s   later  in the  project . The beacon mode is the version under test at the moment.

 

Opera  was  designed  as an alternative  to the  QRSS  transmission  system and  provides  for a  limited  number of characters to  be  transmitted by   a  serial  single  keyed  tone  , as  is  QRSS   or  live  CW, 6 at the  moment.

 

It is  live  ?data? mode and  there  is  no  requirement  for  time  synchronisation  of the  tx/rx  station .

 

The  mode  can  be  transmitted  by  any  transmitter  SSB/CW , there  being  provided  a  keyed tone  and   Comm.  Port  CW   key interface 

 

There  is  a  windows ?gui? interface   and  the  requirement for   RX audio  feed,  based  round 1500 Hz , Tx  audio  at 1500 Hz may  also  be  used to  drive  a  audio/rf conversion ,  changes  of  Tx  audio tone  prevent collisions, and the  software scans  for a  slot of minimum noise . to  place the  TX carrier  in.

 

If the  CW key option is  used, then the  Tx frequency  is  selected  by the  Tx master oscillator  only.

 

Once a signal is decoded, the decode-spot is distributed to other web-connected   users, future development  will  link to the  PSK-Reporting  network .

 

 

OPERA  is coded  at the  moment  for  136  and  500 Khz   and  still  under  development.

 

As  a  basic  out  line  the  system (at the  moment) codes  the  six  characters  of the  call  sign  and  transmits  them as a  serial  ?pulse?  train using  either  conventional  audio  to  RF  translation  , or  by   the  use of  a  COM port  and  transistor  keying  cct  that  simply  replaces the CW key ,

 

Reception, as the  data   is  spread  out along  a  time  line , decoding  is completed  during the  final  stages of the  transmission , due to  this  ,,it  is not  possible  to  include a  receive  progress  monitor, however the  system  will  track and  decode  multiple transmissions  of  both time  bases simultaneously

 

 

Transmit times are  used to  denote  the  mode  

 

500 Khz 

 

2        Minuets  

16      Minuets

 

136 Khz

 

8          Minuets  

65        Minuets

 

 

 

S/N, The  mode  is  capable  of  decoding  under the  noise level  , beyond  that  of  WSPR  or the  ROS-MF-2   system with a  maximum  data  loss of  33%  before  the  decode Fails.

 

Opera 2     similar to WSPR


Opera 8     6dB better than WSPR.

 

Opera 65   9 dB better than Opera8,

 

 

 

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