Joe, I have derived both Contestia and RTTYM from Pawel's code. You
may look at the sources at http://pocketdigi.sourceforge.net

Try to revert the bits before they are fed to the baudot decoder.

73, Vojtech OK1IAK

--- In [email protected], "Patrick Lindecker" <[EMAIL PROTECTED]>
wrote:
>
> Hello Joe,
> 
> What is sure is that there is no other differences that the ones I
gave in the "RX/TX modes selection and their descriptions" chapter, so
modifications on:
> * Block size (symbols)
> * Scrambling pseudo-random sequence
> * Scrambling shift (in number of bits of sequence right rotation)
> * Characters set 
> 
> Try first to change from Olivia to Contestia. It is the simplest, as
RTTYM adds a switch management, contrary to RTTYM.
> 
> Then try in reception generating Contestia, without noise. You must
decode it. Then adjust the different parameters of your code to decode
low S/N Contestia signals.
> 
> 73
> Patrick
> 
> 
> 
> 
> 
> 
> 
> 
>   ----- Original Message ----- 
>   From: Joe Veldhuis 
>   To: [email protected] 
>   Sent: Wednesday, September 27, 2006 6:38 PM
>   Subject: Re: [digitalradio] Re: Implementing Contestia/RTTYM,
could use some advice
> 
> 
>   Patrick only gave an outline of the differences between Olivia and the
>   derivative modes. What I am looking for is some pointers on the actual
>   task of modifying the templates to implement those differences.
> 
>   I tried implementing RTTYM by changing the "BitsPerCharacter" and
>   scrambling code/shift parameters in Pawel Jalocha's reference code
(and
>   then passing the output through a Baudot>ASCII routine), but that was
>   apparantly not enough, since I don't get any output from the
demodulator.
> 
>   -Joe, KD8ATU
> 
>   jhaynesatalumni wrote:
>   > I haven't looked yet, but you might look in the MultiPSK
documentation,
>   > since Patrick recently implemented those modes in his program
and may
>   > have written them up.
> 
> 
>    
> 
> [Non-text portions of this message have been removed]
>

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