This cheaper eBay antenna I have says it is for 1575.42MHz. Is that anywhere near what it should be?
-Don -------------------------------------------------- -----Original Message----- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of David Sent: Saturday, January 07, 2012 11:17 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Getting my Rockwell D200 GPS to work I am not suggesting this as a replacement for a proper GPS antenna. I am suggesting it as a inexpensive sanity check. The loss from receiving a circularly polarized signal with a linearly polarized antenna (or the reverse) is 3db. On Sat, 7 Jan 2012 17:29:54 +0100, Azelio Boriani <azelio.bori...@screen.it> wrote: >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. _______________________________________________ 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.
