Hi, In car radio capacitive antennas are used. The required LNA rejection for the power line frequency is in the order of 100dB.
henk On Aug 10, 2008, at 15:16, Alan Melia wrote: > Hi Didier, thanks for that idea, yes they were all "pucks" all > Garmin two > intended for marine use and one was a old Garmin GPSIIplus with a mag > "puck". I have a Trimble Palisade that I have not got round to > working on > yet, but I understand that there are problems putting this version > into NMEA > mode...so will have to be careful. > > Thanks Alan G3NYK > > ----- Original Message ----- > From: "Didier Juges" <[EMAIL PROTECTED]> > To: "'Discussion of precise time and frequency measurement'" > <[email protected]> > Sent: Sunday, August 10, 2008 12:52 PM > Subject: Re: [time-nuts] GPS shielding by power lines? > > >> Alan, >> >> I don't believe you have said what type of antenna you are using. >> If you > are >> using a true timing antenna (Symmetricom, Trimble Bullet) I would >> expect >> little or no direct effect from the power lines, but if you are >> using a > puck >> or other inexpensive commercial antenna (which have little or no >> filtering >> or shielding), you may well be affected directly by the field from >> the > power >> line on the antenna itself. The Thunderbolt itself should have enough >> filtering to protect you from a direct effect, the Thunderbolt has >> been >> designed to be co-located with other equipment, particularly cell >> transmitters, so I would expect it to be fairly immune to stray >> fields. >> >> Didier KO4BB > > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/ > time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
