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And of course , there is a PIC code
generator in the windows software ,
that can be used , Andy g4jnt has a
post about using it for driving a
standalone beacon..he did run op34 / 64 on 136 as
a beacon early in the year ..The only thing
that is missing is the internet beacon
alert , clock accuracy of 0.2% is
needed to achieve the lowest s/n decodes , Eddie
G3GZO and I think Pete M0FMT are using
standalone keying devices
73 -G.
clock times for modes :-
Opera 05: 0.128 s
Opera
1: 0.256 s
Opera 2: 0.512
s
Opera 4: 1.024
s
Opera 8: 2.048 s
Opera
32: 8.192 s
Sent: Monday, July 16, 2012 11:18 PM
Subject: Re: LF: opera coding demistified
Stefan Schaefer wrote
> G.., i have done it. Downloaded ... to my LF PC.
Still can't belive it...
... well, I haven't ;-) Out of curiosity, I have
instead implemented Guido's excellent guide on Opera
encoding
in a little Basic program, which outputs the
110... keying sequence for any given callsign.
And it works! For a quick on
air test, I decided to use SpecLab's test signal generator, modulated by an
arbitrary waveform which can be loaded from a text file. To fit
to the required data format, I edited the sequence by
zero-padding from 239 to 256 symbols, then replacing every "1" by two
lines of "32767", and every "0" by two lines of "0", giving
512 samples total. For "Op4" speed, the AM modulator
period was set to 0.256*4*256 = 262.144 seconds. Audio output was used to key
my TX on 478.63 kHz. I sent for strings on Saturday night 21:30
to 21:47, and within a few minutes, pskreporter.de showed spots from DF2JP,
G8HUH, ON6EO and DD7PC.
In case you would also like to
send Opera without "his master's software", or associate obscure received
sequences with possible candidates, the little program and sourcecode
is at
Best 73,
Markus (DF6NM)
Sent: Friday, February 17, 2012 11:48
AM
Subject: LF: opera coding
demistified
PE1NNZ seems to have demistified the opera coding,
those interested can read the attached file.
73, Rik ON7YD - OR7T
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