Hi Nothing is ever simple if you dig deep enough:
http://www.jensign.com/RG58U/ http://www.cliftonlaboratories.com/the_curious_case_of.htm Bob > On Jan 23, 2017, at 10:13 AM, REEVES Paul <[email protected]> > wrote: > > Hi David, > > Surely the impedance of the cable is only affected by the ratio of the inner > conductor and outer conductor diameters modified by the internal dielectric > constant, nothing to do with the frequency of operation. You might well have > problems converting the larger diameters down to a suitable size for the > connectors at the higher frequencies though.... > I thought that the HP cabling for the 8510 series VNAs was air spaced but I > might well be wrong - I just tried not to damage them :-) > Regards, > > Paul Reeves > > -----Original Message----- > From: time-nuts [mailto:[email protected]] On Behalf Of Dr. David > Kirkby (Kirkby Microwave Ltd) > Sent: 23 January 2017 13:26 > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Thermal effects on cables > > On 13 January 2017 at 06:52, Ole Petter Ronningen <[email protected]> > wrote: > >> Hi, all >> >> The question of phase shifts in cables pops up every now and then on >> this list - I stumbled across a good table of measured phase shifts >> with temperature in different cable types in this paper: >> http://www.ira.inaf.it/eratec/gothenburg/presentations/ERATEC_2014_ >> PresentationWSchaefer.pdf >> that I though would be of interest to others. >> >> > I've like to know how VNA cables compare. They are expensive enough - a > couple of cables around 600 mm long (24") for my VNA are over $5000. They are > much larger diameter than normal cables, but much more flexible too. > The construction is obviously very different. Since mine are designed for use > to 26.5 GHz, the internal diameter of the outer conductor can be no more than > a couple of mm, yet the overall cable has a diameter of about 15 mm. > > Dave > _______________________________________________ > time-nuts mailing list -- [email protected] To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
