Hi If you really want to work out the delays through all of this GPS "stuff" ahead of the RF -> PPS conversion, a VNA is about the only good way to do it.
Bob > On Aug 21, 2016, at 6:59 PM, Dr. David Kirkby (Kirkby Microwave Ltd) > <drkir...@kirkbymicrowave.co.uk> wrote: > >> On 21 Aug 2016 03:19, "Attila Kinali" <att...@kinali.ch> wrote: >> >> Moin, >> >> I stumbled over a new open hardware/source VNA design: > http://hforsten.com/cheap-homemade-30-mhz-6-ghz-vector-network-analyzer.html >> >> Unlike other designs out there, this one is very well done and has very >> little room for improvement, without increasing the price considerably. > > I am not convinced that this is time-nuts related, although I am sure many > time-nuts either have a VNA or would like one. Such a project needs its own > forum. > > That said, I don't know why the author is using directional couplers. A > bridge is much wider bandwidth. It is more lossy though. > > The software is I believe the tricky part. The VNWA software is very > sophisticated, with a lot of useful features like it can design matching > networks, The software in the PNA-X is very sophisticated too, but in > different ways. > > I don't know what the author uses, but Qt seems like best choice to me, > which can be be built on OSX, Linux and Windows. > > For many measurements power levelling is not required, so that bit could be > dispensed with. > > The author seems of the opinion that a lot of the hardware imperfections > can be corrected in software. Thak is true, but the the residual errors > that remain are a function of the quality of the hardware. > > Anyway, it is an interesting project, but personally if I were going to > go to the effort of building a 2-port VNA, I would build one with 4 > receivers. > > Dave > _______________________________________________ > 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.