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Re: 1200/2400 hertz Mozhaetz telemetry

Yikes, this sure stired up a cloud of brain dust!

For those who don't know, the Kansas City Standard was used
in the Barnstorming early days of personal computing, before
what we now call a PC was invented.  It was used to record
programs and data on audio cassettes; hard disks were typically
the size of washing machines, and the floppy disk (8 inch!) was
too still expensive for most.

As I recall, the format used 8 cycles of 2400 hz for a "1", and
4 cycles of 1200 hz for a "0".  A simple modem did the decoding.
The resulting 1200 baud data stream was sent in to a standard
async serial port.  You would literally "play" your program from
the tape into your computer to load it.  It worked quite well.
They even published software on thin plastic sheets that you
put on your phonograph at 45 rpm.  Called them "Floppy ROMs"...

We now return you to the 21st century...

Greg  KO6TH

>From: Cliff Buttschardt <cbuttsch@slonet.org>
>Reply-To: cbuttsch@slonet.org
>To: amsat-bb@amsat.org
>Subject: [amsat-bb] 1200/2400 hertz Mozhaetz telemetry
>Date: Mon, 02 Dec 2002 01:49:43 +0000
>A number of members have indicated that the telemetry on the Russian
>Mozhaetz satellite sounded like two tone FSK, 1200 and 2400 hertz.
>      This might be the very old "Kansas City standard" used by computer
>people when only tape recorder data storage was available economically.
>This standard was most forgiving and easy to implement. We will have to
>look back many years for information on this one!!   Cliff K7RR
>Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
>To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org

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