Just take care that GPS signal is right-hand circularly polarized. For those interested in building GPS antennae I recommend the QFH-type antenna: quite complex but it is the same antenna actually used to transmit from the birds.
On Sat, Jan 7, 2012 at 5:02 PM, David <davidwh...@gmail.com> wrote: > I have done the same thing with an amplified patch antenna facing out > the window. > > I wonder in this case if making a rough 1/4 wave antenna out of a very > short feedline would be enough for a cheap outdoor sanity check. > > On Sat, 7 Jan 2012 14:21:09 +0000, shali...@gmail.com wrote: > > >I test all my GPS receivers with a hockey puck type antenna attached to > the wall in my hamshack, which is upstairs, but under the ceiling and the > roof and I have never had one fail to lock within reasonable time. With > this setup, Thunderbolts occasionally go on holdover, but never for very > long. > > > >Of course, when I plug them in the external Symmetricom antenna, they > typically see more satellites and don't go into holdover. > > > >I am in Northwest Florida, so probably at a lower latitude than most of > you, so the same setup farther north may not work as well. > > > >Didier KO4BB > > > >Sent from my BlackBerry Wireless thingy while I do other things... > > > >-----Original Message----- > >From: Azelio Boriani <azelio.bori...@screen.it> > >Sender: time-nuts-boun...@febo.com > >Date: Sat, 7 Jan 2012 02:00:21 > >To: Discussion of precise time and frequency measurement< > time-nuts@febo.com> > >Reply-To: Discussion of precise time and frequency measurement > > <time-nuts@febo.com> > >Subject: Re: [time-nuts] Getting my Rockwell D200 GPS to work > > > >Absolutely yes, the antenna must see the sky, not the ceiling. Even very > >sensitive GPS receivers must have a good view of the sky for the first > fix, > >then you can bring the antenna indoor. You can try positioning the antenna > >very near a window for just a test but better a good view. The car roof is > >okay but you must wait several minutes (12 minutes at most) to let the > >receiver download the almanac. > > > >On Sat, Jan 7, 2012 at 1:54 AM, Don Lewis <dlewis6...@austin.rr.com> > wrote: > > > >> Maybe I didn't take positioning seriously. > >> > >> The antenna is currently on a shelf above my workbench, ....there is a > >> ceiling and an upstairs above it. Then the roof. > >> > >> Is it very critical to be outside in order to 'see' the sky? > >> > >> I did take it out once and set the antenna on my car roof, ....but > still no > >> satellites. > >> > >> > >> -Don > >> > >> From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On > >> Behalf Of bownes > >> Sent: Friday, January 06, 2012 6:49 PM > >> To: Discussion of precise time and frequency measurement > >> Cc: Discussion of precise time and frequency measurement > >> Subject: Re: [time-nuts] Getting my Rockwell D200 GPS to work > >> > >> Step one...is the antenna in a location where it can see they sky? > >> > >> Sorry if it is a stupid question but you already said it was plugged > in. :) > >> > >> On Jan 6, 2012, at 19:24, "Don Lewis" <dlewis6...@austin.rr.com> wrote: > >> > >> > Can someone please give me some pointers (my first time with a GPS > >> module). > >> > > >> > A little hand-holding, pls. > >> > > >> > I bought three of these Rockwell D200 GPS receivers. (It's little GPS > PWB > >> > with an antenna connector and pins for connecting to the RS232- PC) > >> > > >> > All three 'appear' to work the same way (no apparent capture of > >> satellites). > >> > > >> > Here's what I have: > >> > > >> > 1. VisualGPS installed and running. > >> > 2. A small USB-RS232 card installed and appears to be operational. > >> > 3. Small GPS active antenna plugged in. > >> > 4. VisualGPS monitor just repeatedly displays: > >> > $GPGGA,,,,,,0,00,,,,,,,*66 > >> > 5. I think I understand this to be NMEA code to mean no satellites > >> have > >> > been acquired. > >> > 6. The Rockwell D200 draws ~180ma (5V) with no antenna and ~190ma > with > >> > the small active antenna plugged in. > >> > > >> > What am I doing wrong? Other than maybe cheap china gps' and > antenna??? > >> > But it is what I could afford and thought it would be cheap to learn > on. > > _______________________________________________ > 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.