[time-nuts] Spectracom 8170 -> SWCC clock
jxh at jxh.com
Fri Jan 20 17:23:16 EST 2012
I have a Spectracom 8170 in the living room (who doesn't?), and a Western Union
time-service clock, a.k.a SWCC clock -- a nice one, in a 3-foot-high wood case.
I've been watching TV with this combination for years and years but never got
around to feeding a pulse from the 8170 to discipline the other one. Now that
Western Union no longer provides the service. :-) But it just begs to be done.
I did draw up a TTL circuit, once (on a napkin, naturally, which I have now
misplaced), that could live inside the 8170. I figured out the minimum number
of inputs needed to detect when the MM:SS LED displays said 00:00 (for one
second). It would close a relay, which could feed the winding-battery power to
the hour-set solenoid down a pair of wires from 10 feet away. But I never built it.
A little over a year ago the TS clock was getting gummy and free-running slower
and slower, so I sent it to the clock hospital. It's back and free-running
nicely, so maybe it's finally time I did this. Anyone got a better idea than my
little TTL circuit, on a breadboard inside the 8170? I'd like to get it across
the rear panel without cutting a new hole, if I can avoid it. But maybe the
right connector would do. Another time-code receiver in the TS clock, e.g. a
GPS module that provides a relay closure for 1 second on the hour (if such
exists) might be neater. But the living room faces north.
More information about the time-nuts