Right. The fixed location apps are not all that hard. But the mobile ones are going to be a big problem.
Not to mention getting them certified for the application. The GPS you have in your car is not certified for life critical applications. The one I have in my ambulance is. And let's not even get into commercial flight certification. A technical issue, but one verging on politics. To answer your question #3, it is one of two specific kinds of attenuator. Generally a band-pass (passes the GPS frequency only) or notch filter (attenuates the undesired frequency only). As Jim said, these things don't only impact the desired frequency. For more information, take a look here: http://en.wikipedia.org/wiki/Band-pass_filter Short answer, yes it can be done, in a limited set of applications. Until you reach layer 8. Bob On Fri, Sep 30, 2011 at 10:02 AM, Marco IK1ODO -2 <ik1...@spin-it.com> wrote: > At 15:44 30-09-11, Jason wrote: > >> To filter out the L2 signal, would an actual GPS receiver have to be >> replaced / modified? >> >> Or would a more simple and cheaper alternative be to get a new antenna >> (with fancy filtering) to replace my existing roof-top >> antenna and expect all my old equipment to be happy? > > I think that a new antenna/filter/amplifier unit would be ok. But the > problem is the installed base of receivers, including all those costly units > used for geodesy or navigation, that have embedded antennas. Those will be > hard to modify. > > 73 - Marco IK1ODO > > > > _______________________________________________ > 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.