Hello to the group. Been a while. Wanted to update the group on the WWVB remodulator that allows receivers like the spectracom 8170, Netclock 2 and Truetime DC60 to work with the new BPSK signal and display accurate time.
The plan had been to leverage the accurate d-psk-r 60 Khz clock for the remodulator. But Its been a while and I simply decided to build the whole remodulator up in a separate 1 RU box. Took no time at all. Hardest part was drilling holes for BNC connectors. I had a concern on frequency stability and the fact is the internal crystals of these radios is +-40 Hz. Simply not an issue. The DC60 would loose lock frequently. Turns out the DC60 had a bad molex connector on the 5 VDC supply. Fixed issue problem gone. However I did upgrade the 60 Khz clock from the pure crystal that did work to a 15.360 Mhz oscillator (Vectron) divide by 256 using a 74HC393 chip to feed the modulator a 74HC08. I used all 4 sections of the 08 to create 2 outputs that split to feed 6 total ports with 1.8K ohm pull downs for those radios that sense a antenna. All of the wwvb clock units work and I have 2 spare ports. Updated the schematics and if anyone wants a set let me know. What really motivated me was several thread with another time nut and I decided, why wait build a separate box and be done. Also will send a separate email discussing the small atomic clocks and how to use them for the remodulator. Regards Paul WB8TSL _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.