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    SubjectRe: NEWSFLASH! Linux ported to Commodore VIC-20!!
    Date
    Nathan Hand <nathanh@chirp.com.au> writes:
    > The maths is a lot harder than that. You'd be lucky to get 5MB on
    > a C-90, even with top quality record/playback heads.

    5 MB on a C-90?? That's only 460 Bytes per second (on each audio channel).

    Given that an audio tape has significantly more bandwidth and a somewhat
    better s/n ratio than a telephone line, and that you can get 4200 bytes/sec
    (at a nominal modem speed of 33600) over the latter, your 5 MB are WAY too
    low. Let's see, phone line has 3 kHz Bandwidth, the tape has around 15 kHz
    => five times better => 45 MBytes on a C-90, disregarding the higher s/n
    ratio for which I don't have numbers offhand. Hmm, 6 bits on the phone line
    vs. 12 for the tape? That'd be 90 MBytes per C-90 tape.

    The math required to actually decode the stuff might, however, be somewhat
    beyond your ordinary CPU if you want to decode the stuff in real time.
    (You need to. The audio from this experiment needs around 650 MBytes, and
    if you have that much space around, sell that spare disk and buy a decent
    tape drive instead... :-)

    It's already a problem for software Fax receivers, and they do only
    14400 or 9600 baud.

    --
    Matthias Urlichs | noris network GmbH | smurf@noris.de
    The quote was selected randomly. Really. | http://www.noris.de/~smurf/
    --
    May you live all the days of your life.
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