Actually as I think about it from the earlier part of the thread. Locking to the carrier with a 2-4 second time constant removes the phase modulation since its only in the first 200 ms. The 0 Phase is 800 ms in length or more for all bits. Now to find some nice coils for 162 KHz. Regards Paul
On Mon, Mar 6, 2017 at 8:30 PM, paul swed <[email protected]> wrote: > A bit more reading if you block the phase comparison from -50ms to 150ms > of the tick you get a 0 carrier phase no modulation. That also explains why > I thought I could here some sort of phase modulation because there is. > So as an example if you use a GPS tick its really simple to block the > phase changes and only measure the 0 phase carrier. Essentially a 200 ms > carrier gap per second. > Thats quite a clean format you have to work with. > Regards > Paul > WB8TSL > > > On Mon, Mar 6, 2017 at 8:19 PM, paul swed <[email protected]> wrote: > >> I checked out 162KHz at 2000 local and now have what I believe to be TDF >> using the 67 ft vertical antenna. I am reading -82 dbm near Boston in the >> US or 3400 miles. A comfortable signal at least in the winter. As a >> comparison wwvb at 60 KHz is -77dbm some 2000 miles but also not at a 2 MW >> power level like TDF. >> >> Since I had not heard TDF before I listened to Pieters online SDR radio >> to see what to listen for. The easiest point to notice is the 59 second >> phase. Its funny that also seconds 0-10 should be the same phase but it did >> not seem to be true. Unless what I am hearing is the local oscillator of >> Pieters SDR radio. >> >> So thanks for sharing some new knowledge with Time-nuts. >> Regards >> Paul >> WB8TSL >> >> On Mon, Mar 6, 2017 at 1:46 PM, Pieter-Tjerk de Boer < >> [email protected]> wrote: >> >>> >>> On Sun, Mar 05, 2017 at 10:42:52PM +0000, Iain Young wrote: >>> >>> > That's TDF from France. Their equivalent of WWV/MSF/DCF. >>> >>> > Average phase and frequency deviation is >>> > zero over 200msec (see link above for details) >>> >>> This is not quite correct, since the transmitter does not just carry the >>> time data (one bit per second, in the first 200 ms of the second), but >>> also some more data during the next 700 ms of each second. >>> The latter data is coded in a way which does not guarantee that the phase >>> or frequency average is zero other than when averaging over the entire >>> 700 ms block. >>> Then again, I've been told that although there is a nicely defined >>> framing >>> format, in reality it has only ever transmitted idle frames, so in >>> practice >>> it's a fixed pattern which repeats every minute and thus could be >>> cancelled >>> for use as a frequency reference. >>> >>> I have a live online decoder for TDF's signal at >>> http://websdr.ewi.utwente.nl:8901/tdf/ >>> >>> Regards, >>> Pieter-Tjerk, PA3FWM >>> >>> _______________________________________________ >>> time-nuts mailing list -- [email protected] >>> To unsubscribe, go to https://www.febo.com/cgi-bin/m >>> ailman/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.
