As far as I know, my friend's GPS dropout problems have been associated with simple clouds with no rain (at least no rain reaching the surface).
Dana On Wed, Oct 23, 2019 at 2:00 PM Tim Shoppa <tsho...@gmail.com> wrote: > I don't think clouds is the direct cause, but of course clouds in the sky > can be correlated with wet foliage. > > Especially if the GPS Field Of View has a lot of angle taken up by tree > canopy, wet foliage can substantially degrade not just GPS reception but > other VHF and UHF signals. > > I notice this the most in the fall when the leaves are large and mature and > are start losing their waxy coat, but have not yet fallen. > > Even after all the leaves have fallen, wet branches have attenuation > ability as well. > > Some research papers have connected windy conditions with UHF attenuation > especially deep fading as well ( > https://ieeexplore.ieee.org/document/1337081 > ). > > Tim N3QE > > On Tue, Oct 22, 2019 at 2:01 AM Dana Whitlow <k8yumdoo...@gmail.com> > wrote: > > > A friend of mine living in SE lower Michigan recently bought > > a Geppetto GPS clock, and swears that it tends to lose > > satellite lock on cloudy days but does OK on sunny days. > > > > He is admittedly using a very poorly-sited antenna, > > placed in a window because his house has aluminum > > siding. He reports that his Garmin handheld GPS > > has much less trouble acquiring and maintaining lock > > on cloudy days than does the Geppetto, but still tends > > to show higher levels of probable position error on > > cloudy days. I don't yet know if he takes the Garmin > > outside for these comparisons. > > > > Is this a real phenomenon, or is my friend just imagining > > things? > > > > Meanwhile I think I have finally persuaded him to install > > the antenna outside on the roof. > > > > Dana (K8YUM) > > _______________________________________________ > > time-nuts mailing list -- time-nuts@lists.febo.com > > To unsubscribe, go to > > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.