Path: utzoo!attcan!uunet!lll-winken!lll-tis!helios.ee.lbl.gov!pasteur!ucbvax!decwrl!hplabs!hpl-opus!hpccc!hp-sde!hpcuhb!hpcllla!hpclisp!hpclkms!ken
From: ken@hpclkms.HP.COM (Kenneth Sumrall)
Newsgroups: comp.sys.atari.8bit
Subject: Re: Was: Re: Need a cassette tape drive.
Message-ID: <1270008@hpclkms.HP.COM>
Date: 28 Oct 88 17:35:06 GMT
References: <31302@bbn.COM>
Organization: HP NSG/ISD California Language Lab
Lines: 24

/ hpclkms:comp.sys.atari.8bit / BobR@cup.portal.com (Bob BobR Retelle) /  8:58 pm  Oct 21, 1988 /
>
>A normal audio cassette recorder  *will*  work, but not very well.  The

I really doubt it.  Just as someone said in a previous note, the Atari uses
FSK modulation to record on the tape.  The computer modulates the signal when
it sends it out, but the tape recorder de-modulates the signal before it sends
back digital data to the computer.

However, if you want to build a converter for a normal cassette deck you can
get the circuit out of the January 1984 issue of Computers and Electronics.
(It was formerly called Popular Electronics.  The magazine has since folded,
so your best bet is to check with your local library.)

The article has a circuit based on the XR2211 FSK demodulator chip, ($2.95 from
Jameco Electronics), and also a circuit to remodulate the signal and copy the
tape on another tape deck.  It also includes a short description of how it all
works.

Good lock if you try building one, and let the Usenet community know how it
works.

Kenneth Sumrall
ken%hpclkms@hplabs.hp.com
...!hplabs!hpclkms!ken