Re: opensource_gps Digest, Vol 65, Issue 1
[email protected] Mon, 07 Feb 2011 23:58:36 -0600 (CST)
| Newsgroups | gmane.comp.hardware.gps.opensource |
|---|---|
| Message-ID | <454608311.753622.1297144716786.JavaMail.root@vms170035> |
--===============5550026821177673572== Content-type: text/html; charset=UTF-8 Content-transfer-encoding: quoted-printable <div style =3D "font-size:12px; font-family:Arial; color:#000000;"><DIV>Hel= lo Siddharth,<BR><BR>To reduce the false alarms try increasing the Threshol= d value, this increases the signal strength required for transitioning to t= he various states.</DIV><DIV> </DIV><DIV>Best regards,</DIV><DIV> = ;</DIV><DIV>Cliff </DIV><DIV style=3D"MARGIN: 5px 0px; BORDER-TOP: #bc= bcbc 1px solid"></DIV><SPAN>On 02/06/11, <SPAN>Siddharth Paliwal<siddhar= [email protected]></SPAN> wrote:</SPAN>Thanks for the reply, Doug and= Mark.<DIV>For my application I require a short length cable only (about 35= cm or so), and I wasn't able to find any resource to get only 2-3 pieces</= DIV><DIV>manufactured so I got it modified by some person who had done it b= efore a few times. I was suggested to use a Network Analyzer</DIV><DIV>to m= easure the return loss and check for impedance discontinuities in the cable= . I am seeing to it and will get back with results.</DIV><DIV><BR></DIV><DI= V>And about the gain values, isn't it possible to reduce False alarms by re= ducing the Threshold value, for which the state transits</DIV><DIV>from Acq= uire/Confirm to Pull-in ?</DIV><BR><DIV class=3Dgmail_quote>On Sun, Feb 6, = 2011 at 1:55 AM, Doug Baker <SPAN dir=3Dltr><<A href=3D"http://webmail.v= erizon.com/webmail/%22http://mailto:[email protected]%22" target=3D_b= lank _djrealurl=3D'"http://mailto:[email protected]"'>dbaker@gpscreat= ions.com</A>></SPAN> wrote:<BR><BLOCKQUOTE style=3D"BORDER-LEFT: #ccc 1p= x solid; MARGIN: 0px 0px 0px 0.8ex; PADDING-LEFT: 1ex" class=3Dgmail_quote>= Hello Siddharth,<BR><BR>Most likely the shortened coax cable is causing the= front-end of the<BR>receiver to be overloaded with too much gain. Th= e cable length that comes<BR>with that Trimble antenna is such that it prov= ides enough attenuation to<BR>work properly with that receiver.<BR><BR>You = may want to try adding some coax back to that antenna to introduce loss<BR>= in order to get the correct amount of gain.<BR><BR>Regards,<BR><BR>Doug Bak= er<BR>GPS Creations, Inc.<BR>PO Box 381272<BR>Germantown, TN 38183-1272<BR>= USA<BR>Cell Phone: 949-547-0608<BR><BR>-----Original Message-----<BR>From: = <A href=3D"http://webmail.verizon.com/webmail/%22http://mailto:opensource_g= [email protected]%22" target=3D_blank _djrealurl=3D'"http://mai= lto:[email protected]"'>opensource_gps-bounces@list= s.psas.pdx.edu</A><BR>[mailto:<A href=3D"http://webmail.verizon.com/webmail= /%22http://mailto:[email protected]%22" target=3D_b= lank _djrealurl=3D'"http://mailto:[email protected]= "'>[email protected]</A>] On Behalf Of<BR><A href= =3D"http://webmail.verizon.com/webmail/%22http://mailto:opensource_gps-requ= [email protected]%22" target=3D_blank _djrealurl=3D'"http://mailto:ope= [email protected]"'>[email protected].= pdx.edu</A><BR>Sent: Saturday, February 05, 2011 2:00 PM<BR>To: <A href=3D"= http://webmail.verizon.com/webmail/%22http://mailto:[email protected]= as.pdx.edu%22" target=3D_blank _djrealurl=3D'"http://mailto:opensource_gps@= lists.psas.pdx.edu"'>[email protected]</A><BR>Subject: open= source_gps Digest, Vol 65, Issue 1<BR><BR>Send opensource_gps mailing list = submissions to<BR> <A href=3D"http://webmail.veri= zon.com/webmail/%22http://mailto:[email protected]%22" targ= et=3D_blank _djrealurl=3D'"http://mailto:[email protected]"= '>[email protected]</A><BR><BR>To subscribe or unsubscribe = via the World Wide Web, visit<BR> <A href=3D"http= ://lists.psas.pdx.edu/cgi-bin/mailman/listinfo/opensource_gps" target=3D_bl= ank _djrealurl=3D"http://lists.psas.pdx.edu/cgi-bin/mailman/listinfo/openso= urce_gps">http://lists.psas.pdx.edu/cgi-bin/mailman/listinfo/opensource_gps= </A><BR>or, via email, send a message with subject or body 'help' to<BR>&nb= sp; <A href=3D"http://webmail.verizon.com/webmail/%22ht= tp://mailto:[email protected]%22" target=3D_blank _= djrealurl=3D'"http://mailto:[email protected]"'>ope= [email protected]</A><BR><BR>You can reach the person = managing the list at<BR> <A href=3D"http://webmai= l.verizon.com/webmail/%22http://mailto:[email protected].= edu%22" target=3D_blank _djrealurl=3D'"http://mailto:opensource_gps-owner@l= ists.psas.pdx.edu"'>[email protected]</A><BR><BR>When= replying, please edit your Subject line so it is more specific<BR>than "Re= : Contents of opensource_gps digest..."<BR><BR><BR>Today's Topics:<BR><BR>&= nbsp; 1. Antenna modification - False Acquisitions problem<BR> = (Siddharth Paliwal)<BR><BR><BR>-------------------------------------= ---------------------------------<BR><BR>Message: 1<BR>Date: Sat, 5 Feb 201= 1 12:35:05 +0530<BR>From: Siddharth Paliwal <<A href=3D"http://webmail.v= erizon.com/webmail/%22http://mailto:[email protected]%22" target= =3D_blank _djrealurl=3D'"http://mailto:[email protected]"'>siddha= [email protected]</A>><BR>Subject: [OpenSource_GPS] Antenna modifica= tion - False Acquisitions<BR> problem<BR>To: <A h= ref=3D"http://webmail.verizon.com/webmail/%22http://mailto:opensource_gps@l= ists.psas.pdx.edu%22" target=3D_blank _djrealurl=3D'"http://mailto:opensour= [email protected]"'>[email protected]</A><BR>Messag= e-ID:<BR> <<A href=3D"http://webmail.verizon.c= om/webmail/%22http://mailto:AANLkTiksePU08GT97nHSkXHbVNZ8dTX%2BB0fKu9zf8v6A= @mail.gmail.com%22" target=3D_blank _djrealurl=3D'"http://mailto:AANLkTikse= PU08GT97nHSkXHbVNZ8dTX%[email protected]"'>AANLkTiksePU08GT97nH= [email protected]</A>><BR>Content-Type: text/plai= n; charset=3D"iso-8859-1"<BR><BR>Hello,<BR><BR>I am running the GPL-GPS cod= e on the GPS600 receiver that I purchased from<BR>GPS Creations. I had to m= odify my Antenna(Trimble) cable length for some<BR>reasons, so I got the ca= ble shortened and got another connector re-crimped<BR>to it. But this modif= ied Antenna seems to have some problems. Now I am<BR>unable to get lock on = satellites, but there seem to be a large no. of False<BR>Acquisitions, in t= he sense that most of the channels (out of 12 available)<BR>now transition = upto the Pull-in state and then fall back to Acquisition<BR>state. And the = code seems to be running perfectly fine with an unmodified<BR>Trimble Anten= na (tracking up to 6-7 satellites !!).<BR>Is there any way to check if ther= e are any problems with my modified Antenna<BR>(probably Impedance matching= problems?) besides running it on the GPS<BR>receiver and checking If I'm a= ble to lock satellites or not. And also what<BR>are the possible places at = which I might have gone wrong?<BR>Any help would be highly appreciated.<BR>= <BR>Thanks.<BR><BR>--<BR>Siddharth Paliwal<BR>-------------- next part ----= ----------<BR>An HTML attachment was scrubbed...<BR>URL:<BR><<A href=3D"= http://lists.psas.pdx.edu/pipermail/opensource_gps/attachments/20110205/bdb= 3e3ed/attachment.html" target=3D_blank>http://lists.psas.pdx.edu/pipermail/= opensource_gps/attachments/20110205/bdb<BR>3e3ed/attachment.html</A>><BR= ><BR>------------------------------<BR><BR>________________________________= _______________<BR>opensource_gps mailing list<BR><A href=3D"http://webmail= .verizon.com/webmail/%22http://mailto:[email protected]%22"= target=3D_blank _djrealurl=3D'"http://mailto:[email protected]= .edu"'>[email protected]</A><BR><A href=3D"http://lists.psa= s.pdx.edu/cgi-bin/mailman/listinfo/opensource_gps" target=3D_blank _djrealu= rl=3D"http://lists.psas.pdx.edu/cgi-bin/mailman/listinfo/opensource_gps">ht= tp://lists.psas.pdx.edu/cgi-bin/mailman/listinfo/opensource_gps</A><BR><BR>= <BR>End of opensource_gps Digest, Vol 65, Issue 1<BR>**********************= ***********************<BR><BR><BR><BR>____________________________________= ___________<BR>opensource_gps mailing list<BR><A href=3D"http://webmail.ver= izon.com/webmail/%22http://mailto:[email protected]%22" tar= get=3D_blank _djrealurl=3D'"http://mailto:[email protected]= "'>[email protected]</A><BR><A href=3D"http://lists.psas.pd= x.edu/cgi-bin/mailman/listinfo/opensource_gps" target=3D_blank _djrealurl= =3D"http://lists.psas.pdx.edu/cgi-bin/mailman/listinfo/opensource_gps">http= ://lists.psas.pdx.edu/cgi-bin/mailman/listinfo/opensource_gps</A><BR></BLOC= KQUOTE></DIV><BR><BR clear=3Dall><BR>-- <BR>Siddharth Paliwal<DIV>Pre-final= year Undergraduate</DIV><DIV>Dept. of Chemical Engineering</DIV><DIV>India= n Institute of Technology, Kanpur</DIV><BR><BR><HR SIZE=3D1><BR>___________= ____________________________________<BR>opensource_gps mailing list<BR><A c= lass=3DparsedEmail href=3D"mailto:[email protected]" target= =3D_blank _djrealurl=3D"mailto:[email protected]">opensourc= [email protected]</A><BR><A class=3DparsedLink href=3D"http://lists.= psas.pdx.edu/cgi-bin/mailman/listinfo/opensource_gps" target=3D_blank _djre= alurl=3D"http://lists.psas.pdx.edu/cgi-bin/mailman/listinfo/opensource_gps"= >http://lists.psas.pdx.edu/cgi-bin/mailman/listinfo/opensource_gps</A><BR><= /div> --===============5550026821177673572== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ opensource_gps mailing list [email protected] http://lists.psas.pdx.edu/cgi-bin/mailman/listinfo/opensource_gps --===============5550026821177673572==--