Memory Tech you don't see very often

Mike Katz bitwiz at
Thu Jan 6 09:45:09 CST 2022

There was also a 1K by 4 version of this tube.

On 1/6/2022 3:03 AM, Brent Hilpert via cctalk wrote:
> On 2022-Jan-06, at 12:19 AM, Joshua Rice via cctech wrote:
>> Not cost effective at nearly $10,000! I understand they're very rare, given they were only used for a few years in industry and they're clocking on 3/4 of a century old, but even then, that seems an order of magnitude or two off the real value.
>> Actually, looking them up, doesn't seem they were used in much at all. Seems to have been a bit of a technological dead-end since core memory quickly superseded it with it's (relatively) cheap costs and (relative) ease of manufacturing. I imagine the US gov. probably used them somewhere, since they were a sucker for cutting edge technology of the time.
>> Would be interesting to know how many hours it's got on it
> "Not cost effective" ?  What does that mean in the arena of valuation of historic artifacts?
> No, they didn't go anywhere as a product and apparently only saw use in one machine.
> However, the 'pro' side of such a debate is that they were a very early attempt to produce a fast digital RAM memory specifically for use in Stored-Program Machines, at a time when memory was at the top of the list of problems in development of the first SPMs, and actually before any SPMs had been produced, and weren't a serial technology like drums and delays lines tortured into applicability for the task.
> They are wrapped up in the history of John VonN and the IAS machine, one of the most significant machines in computing history (arguably the most significant).
> There's always opinion and subjective valuation in assessments of history but if one is acquainted with what was going on in that period of 46-50, they are a very interesting and notable development attempt.
>> ------ Original Message ------
>> From: "pbirkel--- via cctalk" <cctalk at>
>> To: "'General Discussion: On-Topic Posts'" <cctech at>
>> Sent: Wednesday, 5 Jan, 2022 At 17:35
>> Subject: Memory Tech you don't see very often
>> Selectron Vacuum Tube: <>
>> Really nice photo-shoot! I wonder what the back-story to this particular
>> tube might be.
>> I don't think that $16.18 shipping would be, um, adequate protection by any
>> measure.
>> Cheap, but not so sure about "cost-effective" .

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