Glass memory?

[Brent Hilpert]

On 2022-Mar-31, at 11:56 PM, Mark Huffstutter via cctalk wrote:
> -----Original Message-----
> From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Brent Hilpert via cctalk
> Sent: Thursday, March 31, 2022 11:53 PM
> To: General Discussion: On-Topic and Off-Topic Posts
> Subject: Re: Glass memory?
> 
> On 2022-Mar-31, at 8:05 PM, Anders Nelson via cctech wrote:
>> Hey all, found this on eBay:
>> 
>> https://www.ebay.com/itm/Corning-Glass-memory-/125087612899
>> 
>> I can't find any info on it - was it some kind of delay-line or magnetic
>> laminate stack?
>> 
>> Interesting!
> 
> 
> Very interesting - there were glass/quartz delay lines used in TV but never seen such before for digital.
> 
> So first guess was it's a SAW device (Surface Acoustic Wave) delay line, but wondered how the path would be long enough for delays needed (path too short for waves too fast).
> 
> Second guess then could be a quartz internal reflection delay line. See pdfPg.9:
> 
> 	https://www.pearl-hifi.com/06_Lit_Archive/02_PEARL_Arch/Vol_16/Sec_53/Philips_Tech_Review/PTechReview-25-1963_64-234.pdf
> 
> The period is right, those Sylvania ICs in the unit place it in mid-late 60s.
> 
> I've analysed a couple of magneto-strictive wire acoustic delay lines so have some feel for properties/numbers there, but don't know how glass/quartz compares.


------------------------

> Here is some pretty good information.
> 
> https://archive.org/details/TNM_Glass_computer_memories_-_Corning_Electronics_20171206_0185
> 
> Mark


Great document!  Yup, internal reflection.