Hi There is also the minor issue of putting the (very thick) layers on in a spiral around the "core". You put one layer on clockwise and the next counter clockwise. Since the materials are quite springy, controlling the whole process through heat treating is a real chore.
Bob > On Aug 25, 2016, at 4:25 AM, Poul-Henning Kamp <p...@phk.freebsd.dk> wrote: > > -------- > In message <1057836989.2088307.1472104857885.javamail.ya...@mail.yahoo.com>, > Br > uce Griffiths writes: > >> You'd need a rather thick copper jacket to shield effectively >> against the 50Hz magnetic field. > > As in: A good-sized fraction of the wavelength if I recall :-) > > Electric fields are so much easier... > > One interesting thing here is that across distances like this, > there would be significant longitudal currents in such a shield. > > Not as bad as metal spanning the Mississippi, but getting there. > > > -- > 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. > _______________________________________________ > 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. _______________________________________________ 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.
