Hi The Costas loop already has the AM component available. There's no need for a second receiver, just wire the AM output over to the output modulator.
Bob On Jun 17, 2013, at 5:57 PM, "David I. Emery" <[email protected]> wrote: > On Mon, Jun 17, 2013 at 02:41:13PM -0700, Burt I. Weiner wrote: >> Chris, >> >> The 8170 was originally intended to be a frequency reference source >> tied to the USFS (United Stated Frequency Standard). It also gave >> the time of day, but I believe that wasn't it's primary purpose. As >> I recall, there were some versions that did not have the clock >> readout and some that had a chart recorder. Back in the 80's I used >> to drool (it was a disgusting sight!) over the Spectracom receivers >> with the chart recorders. At that time I was usuing a Gertsch RLF-1 >> with an external Moseley 680 chart recorder. The remodulator >> precludes it from being used as a frequency standard, but in my >> opinion, so does the fact that WWVB is now phase shifted a bunch. >> >> The 8170 uses a coherent detector and that's where the problem >> lies. While the 8170 still locks to the WWVB carrier, the new BPSK >> scheme causes the detector to output bad data in spite of the >> original dips in the carrier still being present. I had always >> wondered how it was able to pull the data out the noise, but never >> had a manual until just recently. I had naively assumed that the >> WWVB new BPSK scheme would not affect the time of day aspect of the >> 8170. Like I said, I only use it as a clock in my shoppe, and being >> an old dog I don't easily learn new tricks such as looking in a >> different direction for one of the other clocks. > > I suppose I am stating the obvious, but why not combine Paul > Swed's Costas loop and this scheme to output a phase locked 60 Khz > with the right AM modulation ? > > > > -- > Dave Emery N1PRE/AE, [email protected] DIE Consulting, Weston, Mass > 02493 > "An empty zombie mind with a forlorn barely readable weatherbeaten > 'For Rent' sign still vainly flapping outside on the weed encrusted pole - in > celebration of what could have been, but wasn't and is not to be now either." > > _______________________________________________ > 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.
