Hello, I note lots of Defence procedures used in their metrology labs still require a 3458A as a core item, even for more mundane measurements. Defence seemingly are not switching over to newer voltmeters, or writing out the need for a 3458A. While defence are still maintaining old platforms it makes sense to them in keeping the originally specified test equipment in the relevant procedure - so long as HP keeps supporting the 3458A.
ben -------- Original Message -------- > From: "Poul-Henning Kamp" <p...@phk.freebsd.dk> > Sent: Sunday, May 03, 2015 4:58 PM > To: "Discussion of precise voltage measurement" <volt-nuts@febo.com>, "Jan Fredriksson" <j...@41hz.com> > Subject: Re: [volt-nuts] "*WAY* too expensive for even Keysight to redesign" > > -------- > In message <cafownwcwaz3f931thbhx+e2otvt+hbpq3rxtd+gomm9uibs...@mail.gmail.com> > , Jan Fredriksson writes: > > >> Could you say a bit more about this? Did the 3458A not make > >>economic sense for HP at the time? Is nobody buying 8.5s these days? > > It's an interesting historical confluence: 8.5's are the clippers of DVMs. > > 8.5 only makes sense two places: fundamental/high-end metrology > and basic research. > > Everybody else are totally fine with 7.5 and very few actually need > more than 6.5 (specifying the temperature of your aligator-clips > gets old really fast.) > > The 3458A made it possible to validate the josephson junction as > SI voltage reference -- which ironically made the 3458A surplus to > metrology requirements: Now you can generate any voltage you want > on demand. > > That leaves a theoretical market in basic research, but that's a > very small market which will happily pay a phd-theses for a prototype, > but unless its on CERN scale, production runs are never an option. > > -- > Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 > p...@freebsd.org | TCP/IP since RFC 956 > FreeBSD committer | BSD since 4.3-tahoe > Never attribute to malice what can adequately be explained by incompetence. > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. _______________________________________________ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.