Hello Time Nuts, Chris - maybe you can share that if that's something you can share right now.
Jim and Paul, Like Chris pointed out - on that audio board in the design he's worked on - the Line In has L and R channels - the input resistance is higher than for the mic input - but I suppose it's possible to try a BPSK implementation using that as a starting point. There's no separate gain stage for the Line In inputs like for the mic - but it could work - a small preamp that works with the input impedance of the Line In circuitry may be necessary to get a good input signal - but that shouldn't be too hard to add. Also - do the internals of that chip - the https://www.pjrc.com/teensy/SGTL5000.pdf really allow the L/R Line In channels to be treated independently? If so, it should be good to go at least for experimentation. 73's, John AJ6BC On Mon, Oct 12, 2020 at 12:07 PM Chris Howard <[email protected]> wrote: > > I received a good pointer about doing the BPSK implementation > but have just not gotten it done. > > Chris Howard > > > > On 10/12/20 11:02 AM, jimlux wrote: > > On 10/12/20 7:40 AM, paul swed wrote: > >> John really appreciate the pointer. Though it doesn't help wwvb BPSK > >> its a > >> really good intro to SDR and DSP super simple. A good way to get your > >> feet > >> wet. Hmmm is there a parts order soon? :-) > >> Regards > >> Paul > >> WB8TSL > > > > > > And the teensy has plenty of space and speed to implement a PLL for > > doing BPSK demodulation. > > > > > >> > >> On Mon, Oct 12, 2020 at 10:33 AM Bob kb8tq <[email protected]> wrote: > >> > >>> Hi > >>> > >>> The “ideal” antenna solenoid would be a bit longer ( say 2 X to 5X ). > >>> The turns should be spaced apart by a few percent of the length. > >>> ( so turns over 30 or so … not so much …). > >>> > >>> How much better is “ideal” compared to “just get it done?”. At least > >>> from the stories that are told, it is significant. Since all these > >>> antennas > >>> are very small (so non-ideal) it’s a bit of a snail race. > >>> > >>> Bob > >>> > >>>> On Oct 12, 2020, at 3:42 AM, John C. Westmoreland, P.E. < > >>> [email protected]> wrote: > >>>> > >>>> Paul, > >>>> > >>>> Doesn't the post by Chris Howard above appear to be a good/great > >>>> starting > >>>> point? > >>>> Seems like that approach could be extended. > >>>> > >>>> https://github.com/chris-elfpen/Teensy4WWVBsdr > >>>> > >>>> 73's, > >>>> John > >>>> AJ6BC > >>>> > >>>> > > > > _______________________________________________ > > time-nuts mailing list -- [email protected] > > To unsubscribe, go to > > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
