Hi But can you ignore the WWVB signal swing? The beast flips a cycle (or more) as you hit sunrise or sunset. A cycle at 60 KHz is a lot of ppm. Weather this happens fast enough to actually turn it into a tuning issue is the question.
Bob On Mar 31, 2013, at 7:36 PM, Magnus Danielson <[email protected]> wrote: > Hi, > > Uhm, yes. You want your pulling-range to handle all the drift and tempco you > reasonably can assume, and also that of the application and signal. Since the > signal is WWVB in this case, we can ignore that factor. Also, you don't want > to be completely de-tuned from start either. I'm sure John knows this already. > > Cheers, > Magnus > > On 04/01/2013 01:05 AM, Bob Camp wrote: >> Hi >> >> If the VCXO's tuning voltage runs from zero to 5 volts, and the VCXO tunes >> 0.1 Hz / 0.5 volts at 12 MHz, then it has a total range of about 1 Hz at 12 >> MHz. That's about 0.08 ppm of tune range. A generic crystal likely has a >> tempo of 0.1 to 1 ppm / C. My guess is that you will need a bit more tuning >> range on the VCXO to keep things locked long term. Putting your tuning cap >> in series with the varicap should help this a bit. You may also need to add >> a coil in series with the crystal. >> >> Bob >> >> On Mar 31, 2013, at 6:30 PM, paul swed<[email protected]> wrote: >> >>> Thanks John. >>> >>> >>> On Sun, Mar 31, 2013 at 5:21 PM, John Ackermann<[email protected]> wrote: >>> >>>> At Paul's request, I've put his document about the PSK scrubber for WWVB >>>> at: >>>> >>>> http://www.febo.com/pages/**wwvb_psk/WWVB%20d-psk-r%**2003302013.pdf<http://www.febo.com/pages/wwvb_psk/WWVB%20d-psk-r%2003302013.pdf> >>>> >>>> John >>>> ______________________________**_________________ >>>> time-nuts mailing list -- [email protected] >>>> To unsubscribe, go to https://www.febo.com/cgi-bin/** >>>> mailman/listinfo/time-nuts<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. >> >> _______________________________________________ >> 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. _______________________________________________ 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.
