Graham take a look earlier in the thread there are details about the teensy. There is actually a lot of hardware out there today for little money. Thats what makes the SDR DSP approach interesting and for me at least the next thing to take a run at. Regards Paul WB8TSL
On Tue, Oct 13, 2020 at 10:31 AM Graham / KE9H <[email protected]> wrote: > There are inexpensive CODECs or A-->D converters that are designed for > audio, that can be clocked up to 192 ksps or 200 ksps with 24 bit > resolution. (Typically 18 or 19 effective bits, 3.0 V p-to-p full scale) > They have built in Nyquist filters that scale with the sampling frequency, > so a Nyquist frequency of 100 kHz is very comfortable for receiving a 60 > kHz signal. They use standard I2S audio interface, although other > interfaces are typically options. > > After that it is SMOP, as they say. (Simple Matter Of Programming). :-) > > --- Graham > > == > > > On Fri, Oct 9, 2020 at 12:58 PM paul swed <[email protected]> wrote: > > > after the bpsk is removed true. I have done that. A simple RC filter and > a > > 100K over 50ohm divider to get the signal to a reasonable level. Add a > > coupling cap because all of the old receivers output a preamp voltage. > > > > On Fri, Oct 9, 2020 at 11:35 AM Bob kb8tq <[email protected]> wrote: > > > > > Hi > > > > > > For a full setup, you could do it a lot of ways. A setup of: > > > > > > Antenna -> front end -> ADC -> MCU -> D/A would be one approach. > Various > > > bits like a local clock also would get into the design. There are > *many* > > > other > > > approaches. > > > > > > ========== > > > > > > There are a lot of D/A’s that will clock in the 100’s of KHz range. If > > you > > > are only > > > trying to come up with an analog of a WWVB signal the “10 bit” D/A’s > > found > > > in > > > some MCU’s would do the trick. In the setup above, the ADC would likely > > be > > > harder to come up with than the DAC. > > > > > > Since you are only trying to come up with a carrier, the need for a D/A > > is > > > not > > > an absolute one. Taking a square wave of some sort and filtering it a > bit > > > would > > > be adequate to drive most of these old WWVB receivers. > > > > > > Bob > > > > > > > On Oct 8, 2020, at 11:42 PM, Hal Murray <[email protected]> > > wrote: > > > > > > > > > > > > I assume it needs an antenna, front end, and D/A. > > > > > > > > What's available in the way of D/A that's good for 60KHz? Is the > > > problem > > > > easier if the D/A box has external clocking? > > > > > > > > -- > > > > These are my opinions. I hate spam. > > > > > > > > > > > > > > > > > > > > _______________________________________________ > > > > 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. > > > _______________________________________________ > 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.
