Many of the old receivers use them spectracoms come to mind. They are big units and +- 40 Hz BW and I am totally unaware that they can be found today. That also goes for nice transformers and inductors to build higher Q circuits. I built a opamp chain and it worked well but those crazy amps do draw power. I like the ua consumption level. But thats a personnel preference.
I used the 60 KHz watch Xtals and its in the schematics of the WWVB rcvr I released to time-nuts a year ago. These little crystals are interesting to work with and available from China 25 xtals for a few $ at the pay site. I purchased 2 packs so that I could sift through them. The trick is to very very lightly load them. I could learn much more about them actually. They seem useful overall. The first re-modulator used them directly as the 60 KHz source. I stepped up to the 15.360 MHz osc only because I believed they were not accurate enough and that turned out not to be the case as I found. The other comment to note is that these xtals cause an actual signal gap at the phase transition. Because at that point the signal is actually 2 X 60 Khz. The crystal gaps for at least 8 cycles from what I have seen. Regards Paul WB8TSL On Sun, Jun 29, 2014 at 6:39 PM, Martin VE3OAT <[email protected]> wrote: > John Reed wrote : > > > > > By the way, my 5 section synchronous filter is an LC with > > op-amps between each stage to bring the gain up for the > > squaring chip. It has a 2 KHz -6 dB bandwidth at 60 KHz. > > > > John, have you thought of using a single 60.0 kHz crystal as a bandpass > filter? > > I can't remember which receiver it was, but I think one of the old > commercial WWVB receivers used a crystal as the tuning element. > > ... Martin VE3OAT > > > > > > > _______________________________________________ > 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.
