Re: LF: Sending Opera with SpecLab

[wolf_dl4yhf <dl4yhf@freenet.de>]

Greetings all,
(and apologies to Markus for juming in so quickly..)

The principle described by Markus is only for transmission.
To take place of the DS option, i.e. for RECEPTION, spectrum lab would have to modified to some extend, last not least it would need an 'automated' method to build the correlation patterns for the DS mode itself.
Since Markus has already provided his opera generator (thanks for that!), it could be modified into a command-line driven tool (exe or dll) which SL could invoke to create the 239-bit message pattern for the correlators. I cannot promise too much yet (being busy from too many other projects) but maybe  when the new 'super-linear', moderate-power, switching mode amplifier is finished I'll have a look at it again.

All the best,
  Wolf  DL4YHF .

Am 27.12.2013 02:00, schrieb Bob Raide:

Markus;
 Can this take the place of DS option used with OPERA? 
 

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From: markusvester@aol.com
To: rsgb_lf_group@blacksheep.org; rsgb_lf_group@yahoogroups.co.uk
Date: Fri, 27 Dec 2013 01:45:14 +0100
Subject: LF: Sending Opera with SpecLab

Today I finally found a simple solution to send Opera sequences from SpecLab's digimode terminal. The nice thing about this is that you can use all of SpecLab's powerful functions, like samplerate correction, adjustable pulse shaping, or high audio frequencies. This seems very useful, especially in the context of possible future VLF Opera transmissions.

 

First you will need to create a text file consisting of the 239 bit 1101... sequence for your callsign. This can be generated from the PIC menu in the original Opera software. Or you can use my little code generator tool at http://df6nm.bplaced.net/opera/opera_generator.zip - simply copy opgen.exe from the zip and type

 opgen mycallsign >opera.txt

into a command window.

 

In SpecLab, open the digimode terminal and configure it for ASK with no encoding, as shown in the attached "_settings" screenshot. The symbol rate has to be set to the inverse dotlength for the desired Opera speed:

 

mode   dotlength    rate

          (seconds) (sym/s)

Op-8    1.024s     0.9766

Op-32   8.192s    0.12207

Op-4H  65.536s   0.01526

 

Shaping time can be selected from hard (0%) to soft (50%) keying. Then enter your desired audio frequency and use "Load TX text" from the file menue to load your opera.txt file. The sequence will appear in the TX window, and the transmission can started by hitting the RX / TX button.

 

Best 73,

Markus (DF6NM)