Could this be one of them Brian? Mike - AA8K On 06/24/2013 06:58 AM, Brian Alsop wrote: > > > Interesting you should mention this. One summer job had me > working at a company that made acoustic delay line memories. > Interesting beasties. You stuck the data in at one end . The > output was connected back to the input to recirculate the data. > One wound the magnetic wire in a flat rectangular box. A > torsional mode was used rather than push/pull. A maximum of > about 50 milliseconds of memory was possible. A special near > zero temperature coefficient wire was used as the medium. One > used either return to zero or non-return to zero data formats. > NRZ logic doubled the memory. Part of the job involved laying > out PCB's by hand for the electronics. IC's were just coming on > the scene. RTL logic was the only thing available. For > military applications "flat packs" were used. Through hole IC's > were used for everybody else. Interesting that flat packs > disappeared for about 20 years until SMT became the rage. > > The company eventually died due to lack of suitable wire and > other memory advances. > > Brian > >

No. I'd say the electronics is several years more advanced. Not the same company. However, the idea and construction is essentially the same. 73 de Brian/K3KO On 6/25/2013 18:23, Mike Naruta AA8K wrote: > > Could this be one of them Brian? > > Mike - AA8K > > On 06/24/2013 06:58 AM, Brian Alsop wrote: >> >> >> Interesting you should mention this. One summer job had me >> working at a company that made acoustic delay line memories. >> Interesting beasties. You stuck the data in at one end . The >> output was connected back to the input to recirculate the data. >> One wound the magnetic wire in a flat rectangular box. A >> torsional mode was used rather than push/pull. A maximum of >> about 50 milliseconds of memory was possible. A special near >> zero temperature coefficient wire was used as the medium. One >> used either return to zero or non-return to zero data formats. >> NRZ logic doubled the memory. Part of the job involved laying >> out PCB's by hand for the electronics. IC's were just coming on >> the scene. RTL logic was the only thing available. For >> military applications "flat packs" were used. Through hole IC's >> were used for everybody else. Interesting that flat packs >> disappeared for about 20 years until SMT became the rage. >> >> The company eventually died due to lack of suitable wire and >> other memory advances. >> >> Brian >> >> > > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > > > ----- > No virus found in this message. > Checked by AVG - www.avg.com > Version: 2012.0.2242 / Virus Database: 3199/5940 - Release Date: 06/25/13 > ----- No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2242 / Virus Database: 3199/5940 - Release Date: 06/25/13