Date   : Thu, 31 Jul 2003 21:13:39 +0100
From   : Tony <kilm02@...>
Subject: Re: Doc Project

On Thu, 31 Jul 2003 20:23:35 +0100 (BST), you wrote:

>> How much bandwidth would such a central server need?. I have a machine
>> connected 24 hours a day and could provide unlimited (well, almost)
>> space but would only be able to handle about 500MB/day. Could still be
>> useful as a complete storage mirror though.
>
>presumably Mark can give us some bandwidth stats when he comes back from
>holiday. I doubt it'll be anything remotely like that much though.
Likely
>holding non-ocr scans online is not such a good idea though!
>
>> From memory, EPROM data retention was expected to be around 10 years
>> but can vary greatly due to storage conditions, background radiation,
>> purity of materials used (so from batch to batch retention could
>> vary). Many eproms I programmed in the 80's are now unusable with bit
>> errors, and some of my floppies have died, usually those with original
>> source code I don't have backups of. I still have teletext and early
>> ramdisk ROM source, along with saved teletext pages from 1983-5, but I
>> daren't try reading them in case I discover they're lost :(.
>
>I think somebody else mentioned to me that they have the teletext ROM
source
>the other week, so that does still exist. Saved teletext pages would be
>interesting! 
>
>I don't think I've ever had a EPROM fail on me yet; I pulled another 40
or so
>ROMs from a batch of toasted machines last week though, so it remains to
 be
>seen what state they're in. 5.25" floppies seem to last remarkably well.
 
>

The eprom failures were probably my fault, knowing how much of a hurry
I was always in they probably weren't on the eraser long enough. The
disks I've lost were mostly due to poor storage conditions in the time
in between them being useful and realising they might be part of
computing history :). Of 2 just tried one had a few errors (0C) and
the other worked OK. Just been reading old teletext pages of the
bailiffs being called in at Imagine..... (July 1984)

A lot of the source code, if it's still there, is of pre-release and
development versions, such as a program we wrote for a company
intending to install BBC's with teletext in motorway cafes to provide
trafic info. If I have a chance this weekend I'll go through them and
see what's survived but they really were abused - no dust jackets in
many cases.
The hardware's survived a bit better and I still have prototypes of
our teletext adapter, half an Electron adapter, ramdisk, eprom
programmer, Master romboard and a couple of others.

Oh and I should still have 2 complimentary trade tickets to the 1985
Acorn user show - somewhere. :)

Tony.

>I'm not sure what the supposed useful life of other ICs is; I'm sure
I've heard
>80 or so years quoted before but I'm not sure where I saw that now.
>
>cheers
>
>Jules
>
>
>=====
>Backward conditioning: putting saliva in a dog's mouth in an attempt to
make a bell ring.
>
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