[time-nuts] WWVB remodulator for the spectracom 8170 the schematic is to large

[paul swed]

OK no schematic. It was 2MB. But it was a scan of my notes. Happy to post
to a sight or two. Can include some pictures also.
Operation is simple the msa 6180 receives wwvb and in my case I tap off of
a wwvb antenna multi-coupler.
Output of the 8160 controls inverters that select a 60 Khz clock signal to
select high amplitude or low amplitude for the bit.
The 60 Khz clock uses another 60 Khz xtal from mouser or digikey.
The system consistently allows the Spectracom 8170 to work. Also my fear of
delay due to this processing is unfounded.
Compareing the wwv audio ticks and tones to the 8170 display I can't tell
the difference. Good enough as they say.
No attempt has been made to filter or shape the cmos output. The 8170
filters do a fine job.
Use a low power regulator to drop the 8170s antenna voltage to 5 volts. The
system draws 13 ma.

Other comments you could use a ferrite rod as the app note states. Or you
could feed power to the old spectracom antenna and use it. Essentially the
remodulator sits in the middle of the coax. This project assembled in a few
hours yesterday. The hardest part is soldering the pesky 16 pin soic to an
expander board.
The 8160 chip is available in the US through a distributor. But really not
sure how thats going to work out.
Literally any wwvb clock chip should be able to do this job. But no one
seems to sell them any more.
Hopefully the schematic will get through to the Time-nuts.
As always no intent to kit anything.
Regards
Paul
WB8TSL