Hi: There's a new Software Defined Radio by RF Space, makers of the SDR-14, called the SDR-IQ. The two key differences are that the new radio will tune down to something like <500 Hz (that's NOT kHz, but Hz) and so will work for LORAN-C and other low end stuff. The -IQ model has a 190 kHz bandwidth whereas the -14 has a 4 MHz bandwidth.
The -IQ has resolution bandwidths down to 0.031 Hz which might make it interesting for the FMT? There's talk of a sync input to allow for pulsed signals. http://groups.yahoo.com/group/SDR-IQ/ http://www.rfspace.com/sdriq.html Using DSP technology might result in a higher accuracy timing receiver? Have Fun, Brooke Clarke w/Java http://www.PRC68.com w/o Java http://www.pacificsites.com/~brooke/PRC68COM.shtml http://www.precisionclock.com Rob Kimberley wrote: >>From my Austron days (and I'm sure technology may have moved a bit since >then), we always reckoned on about 1 microsecond as a fairly good accuracy >for a standalone LORAN-C timing receiver. > >Rob Kimberley > >-----Original Message----- >From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On >Behalf Of John Ackermann N8UR >Sent: 20 January 2007 12:57 >To: Discussion of precise time and frequency measurement >Subject: Re: [time-nuts] US considers shutting down Loran > >Hal Murray said the following on 01/19/2007 11:12 PM: > > >>From http://www.fcw.com/article97298-01-08-07-Web >> >> >> >>>Norman said the Alliance for Telecommunications Industry Solutions >>>(ATIS), whose membership includes all the telecom carriers in the >>>country and equipment vendors, views eLoran as the "only viable >>>alternative to GPS for providing [Coordinated Universal Time] of day >>>and frequency accuracy that is suitable for a telecom primary >>>reference source." >>> >>> >>How good is Loran for timing? What's the right parameter for "good"? >> >> > >When used for frequency measurement, Loran is good to parts in 10e-13/day -- >ie, not much worse than GPS. Of course, that's referenced to the Cesium >clock at the Loran station, so you need to do a little juggling to trace >back to NIST. I believe that as they enhance the stations to the new >hardware, the discrepancy from NIST will be much less. > >I recently got one of the (relatively rare) Austron 2100-T Loran receivers >that do timing; you basically lock the receiver to one of the periodic Loran >pulses that coincides with a UTC second marker and it generates a PPS signal >tracking that. I haven't had a chance yet to run any long-term experiments >to measure its stability, but that's on my list of things to do. (I also >plan to hook it up as a refclock for an NTP server; I'm not sure if there's >another Loran-based stratum 1 server out there today.) > >John > >John > >_______________________________________________ >time-nuts mailing list >[email protected] >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > > >_______________________________________________ >time-nuts mailing list >[email protected] >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > > _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
