On 2022-Mar-31, at 11:56 PM, Mark Huffstutter via cctalk wrote: > -----Original Message----- > From: cctalk [mailto:cctalk-boun...@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.