Frequencies around 15 Hz were common on early 20th century cables,

eric@scace.org said: > Frequencies around 15 Hz were common on early 20th century cables, > depending on the degree of success in compensating for the inherent > capacitance on a cable thousands of miles long surrounded by conductive > sea water. Is the sea water relevant? Does enough energy leak through the shield so that it matters? How well does coax work at low frequencies? -- These are my opinions. I hate spam.

Don't forget, seawater is the return path... > On Mar 17, 2017, at 18:04, Hal Murray <hmurray@megapathdsl.net> wrote: > > > eric@scace.org said: >> Frequencies around 15 Hz were common on early 20th century cables, >> depending on the degree of success in compensating for the inherent >> capacitance on a cable thousands of miles long surrounded by conductive >> sea water. > > Is the sea water relevant? > > Does enough energy leak through the shield so that it matters? How well does > coax work at low frequencies? > > -- > These are my opinions. I hate spam. > > > > _______________________________________________ > 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.

Frequencies around 15 Hz were common on early 20th century cables,

-------- In message <20170317220437.4A4FF40605C@ip-64-139-1-69.sjc.megapath.net>, Hal Murray writes: > >eric@scace.org said: >> Frequencies around 15 Hz were common on early 20th century cables, >> depending on the degree of success in compensating for the inherent >> capacitance on a cable thousands of miles long surrounded by conductive >> sea water. > >Is the sea water relevant? Not in a coaxial cable, unless it gets into the cable. Most telegraph cables where not coaxial and used the sea-water as return path. >Does enough energy leak through the shield so that it matters? How well does >coax work at low frequencies? Coax is near perfect at low frequencies, but the lengths of these cables introduced geophysics as a number of sources of noise. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk@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.