Hello Martin,

8 bit or 16 bits is not the problem, only the algorihm used or the hardware 
processing makes the difference. One of the problem is the automatic 
determination of the speed. Did the old Pakrat determines the CW speed 
itself or do you have to enter it? In the same order of ideas, do you have 
to determine the threshold level or is it automatic?

A comparizon between the old Pakrat and a modern software (Hamscope or 
Multipsk) with the same CW signal would be interesting and if really the old 
Pakrat is much better, it would be very interesting to know more about it 
and why it is better.

73
Patrick

----- Original Message ----- 
From: "martinbradford2001" <[EMAIL PROTECTED]>
To: <digitalradio@yahoogroups.com>
Sent: Monday, October 10, 2005 4:05 PM
Subject: [digitalradio] Re: CW decoding comparison (MPSK, Mixw, Hamscope)


>I have an old PakRatt which seems to do a far better job than any
> modern CW decoder I have tried - its a bit picky about its input
> level but once you have that set that correctly it seems to cope with
> some pretty poor morse... That is software which must be close to
> twenty years old and running on an 8 bit Z80 CPU - we really have not
> come very far, have we? It also does an excellent job of RTTY...
>
> Martin (G8FXC)
>
> --- In digitalradio@yahoogroups.com, Dean Gibson AE7Q <[EMAIL PROTECTED]>
> wrote:
>>
>> Modern communications technology has decoders that can rapidly
> adapt to
>> changing clock rates (floppy/CD/DVD drives are a good example). A
> more
>> significant problem with Morse is rapidly varying signal levels in
> real
>> life communications. However, if the technological effort that goes
> into
>> other communications technologies were put into decoding Morse,I
> assure
>> you that the resultant hardware would do far better than humans.
>>
>> -- Dean
>>
>> On 2005-10-09 09:07, Patrick Lindecker wrote:
>>
>> > Hello to all,
>> > Here is an extract of one of my paper (about CCW).
>> > 73
>> > Patrick
>> > *
>> >
>> > Problems with the automatic decoding of the traditional Morse
>> >
>> > *
>> >
>> > For a computer, Morse is seen as a sequence of bits having
> either "0"
>> > or "1" for value, a bit being as long as a dot.
>> >
>> > For example, the letter "A" (`di dah' followed by a 3 dots
> duration
>> > blank or '- --- ') will be recognized as being the sequence
>> > '10111000', if, conventionally, the value "0" is associated to
> the
>> > absence of carrier and the value "1" to the presence of carrier.
> If
>> > all CW transmissions would be standardized on the characteristics
> of
>> > character keying and speed (say 20 wpm), the decoding would not
> be
>> > complicated.
>> >
>> > However, in the reality, characters are keyed in a more or less
>> > regular way and the speed can be situated between 10 and 50 wpm
> and
>> > may vary during the QSO. So, the decoder cannot rely on a
> definite bit
>> > duration and must then, permanently, determines the more probable
> bit
>> > duration, which makes the decoding difficult. This is why, at the
>> > present time, the CW decoding by Morse specialist is better than
>> > software decoding .
>> >
>> > *__*
>> >
>> > *_Note_*: to equal the human decoding, it would be necessary, no
>> > doubt, to abandon the bit notion and to recognize CCW characters
> in
>> > the same way as characters written by hand are, I mean with
> neural
>> > networks leaning on a learning realized upon a set of different
> types
>> > of keying, speeds and signal-to-noise ratios...a big program!
>> >
>>
>
>
>
>
>
>
>
> The K3UK DIGITAL MODES SPOTTING CLUSTER AT telnet://208.15.25.196/
> More info at http:///www.obriensweb.com
>
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>
>
>
>
>
>
>
>
> 



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