Remembering RAMAC

[Spare]

----- Original Message ----- 
From: "Vintage Computer Festival" <vcf at siconic.com>
To: "General Discussion: On-Topic and Off-Topic Posts" 
<cctalk at classiccmp.org>
Sent: Thursday, May 26, 2005 12:19 PM
Subject: Re: Remembering RAMAC


> On Thu, 26 May 2005, Paul Koning wrote:
>
>>  Al> Or magnetic drums, which did NOT have the access time problems of
>>  Al> tape or cards (but, unfortunately weren't an IBM invention)
>>
>> Did the drum come before RAMAC?
>
> Yes.  Many years (I believe about six).
>
IBM did have a drum based machine before the 305 Ramac.
I believe the model # was 650 and was also known as a 650 Ramac.

The 305 Ramacs we were installing in CT (1957 into the 60's) were 10MB disks 
with avg access time of 600ms.
They were also 'programmed' using  plug-in panels, like the EAM machines, 
407's etc.  and stored code.

Both of these IBM machines still had only punched card input for programs 
and transactions.

I can't remember any hard disks greater then 50MB being available even into 
the late 1980's.

>> An obvious difference is that drums, being head per track devices,
>> always had rather low capacity.
>
> And disks are much more efficient than drums anyway.
>
> -- 
>
> Sellam Ismail                                        Vintage Computer 
> Festival
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