Timex/Sinclair 1000 Tape Loading

Allison ajp166 at bellatlantic.net
Sat Jun 18 16:26:49 CDT 2005

>Subject: Re: Timex/Sinclair 1000 Tape Loading
>   From: Tom Jennings <tomj at wps.com>
>   Date: Sat, 18 Jun 2005 14:02:17 -0700 (PDT)
>     To: "General Discussion: On-Topic Posts Only" <cctech at classiccmp.org>
>     Cc: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
>On Sat, 18 Jun 2005, Gary Sparkes wrote:
>> I'm having a hell of a time getting any program to load, so far I've been
>> Totally unsuccessful.
>You're having a vintage experience. This is unfortunately pretty
>much how it went in 1980, only there was no mailing list for you
>to gripe on :-)
>Audio cassette data systems are notoriously finicky about tape
>speed and volume, then cleanliness, etc.
>You also have to hope that when the tapes were made, they were
>with fresh batteries (or on AC adapter) and the volume was set
>right, etc. It is not only possible, it was COMMON, to make tapes
>that were never readable, even once.
>I recall (now, with prodding, ouch) tense
>rewind/play/SHIT!/rewind/play/SHIT!/... sessions with my
>sole cassette-based storage system.

Actually once I got it right even with the funky MITS ACR it was 
near everytime.  After I dumped that and went to 9600 baud PE 
(Phase Encoded, fast version of tarbel and a few others). That 
and going to saturation recoding it was actually near 100%
and faster if it did fail. Storage was always never enough, 
nor fast enough. Bulk random access storage was the holy 
grail of 1975.

FYI: the funkyest device was an old audio echo drum.  It was 
1.15" high by about 9" diameter with a small AC motor and 20 
staggered heads on two tracks.  I shimmed the heads to form 
5 tracks with two heads (one for read and one for write).
The drum was coated with brown oxide and rotated at around
180 rpm (effective "tape speed of ~84ips).  I figured it 
could hold 1kb per track at around 32k baud.  It did.  
I ended up using that a for a few months (till the 
motor bearings which were poor to start failed.) to store
a whopping 10kbyts with an access time of about 400ms.

I wouldn't mind finding an old drum again.


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