julesrichardsonuk at yahoo.co.uk
Sat Oct 29 10:14:51 CDT 2005
>>Subject: Re: Japanese computers
>> From: Jules Richardson <julesrichardsonuk at yahoo.co.uk>
>> Date: Sat, 29 Oct 2005 14:11:24 +0100
>> To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org>
>>William Donzelli wrote:
>>>>I'll see if I can find them when I get back to the UK and scan any
>>>>interesting bits in.
>>>I am specifically looking for info on the parametron computers of the late
>>>1950s, and the Hitachi AS/6 (may be called a HITAC in a Japanese
>>>context) of the late 1970s.
>>I'm almost certain there was some mention of Parametron, amongst others.
>>Probably way too early for HITAC. I seem to recall an article about a
>>project to build a one mega-word memory unit too, which I suppose was a
>>rather impressive size for then (particularly if you wanted to make it
>>reliable!). Our machines of that era are all around the 4KW mark...
> 4KW was common but even the TX2 was far larger than that and that was
> pretty early transistor machine. By mid 60s machine of size were in
> the 16-64KW range. Keep in mind even the designers of the time understood
> that large reasonably fast randomly accessable memory was a factor in
> computational speed and overall perfomance.
This was 1MW though, so a significant leap forward. Plus I'm pretty sure
it *wasn't* magnetic core either. I can't remember the date range of the
magazines we have, but they're somewhere in the range of mid 50's to mid
60's I believe.
Presumably, alongside any real applications, it was built to showcase
Japanese electronics of the era, and also to provide a testbed into the
reliability of whatever technology was used on a large scale.
> As to large memories by 1962 it was well understood the real problem was
> heat, power and consistancy of the magnetics and they were well on the way
> to a good handle on those. The main enemy was cost. Core was expensive
> per bit.
See above - no magnetics from what I can recall. Cost / heat / power
must still have been major considerations though!
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