[GreenKeys] ascii over radio

[gil smith]

At 08:42 AM 2/25/2005, valerie zeiser wrote:
>I'm enjoying this thread, as with most, but this comment
>really struck me!
>As so much of the activity is now computer generated,
>I wonder why we don't hear ASCII transmissions.
>...
>W6ESE - tonyp
>NNNNZCZC


Hi Tony:

Jim Haynes had an interesting point on ascii-over-radio recently:

>ARRL used to broadcast the bulletins in ASCII, after Baudot and AMTOR FEC.
>I don't know if they still do.
>
>ASCII has never been very popular for amateur use, at least at HF.  The
>lowest standard speed for ASCII machines was 110 baud, nearly 3 times the
>45 baud we use with Baudot at 60 WPM.  And with 11 bits per character
>instead of 7 the bits are correspondingly shorter.  The result is that you
>need about 3 times the filter bandwidth and that means more noise.  And
>then the scourge of HF is multipath, which is worse the shorter the bits
>are.  So the bottom line is you need substantially better signals to get
>good copy with ASCII than with Baudot.
>
>jhhaynes at earthlink dot net





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