> And what do you compare your fancy GPSDO or rubidium reference standard to
in order to make sure they have not encountered a major
> failure?
Several options: (1) CHU is still operating on several HF frequencies that
reasonably cover North America; (2) In the U.S., AM broadcast stations are
required to maintain +/- 20 Hz carrier stability (73.1545). However, nearly
all modern BC transmitters can easily meet 2 Hz, and some are now
phase-locked to a precision standard.
Most modern amateur gear covers the MW band. One could sample several AMBC
stations, throw out the outliers, then calculate a geometric mean and attain
a very accurate reference. Incidentally, some legacy ham-band-only gear
never did cover WWV -- or if it did, it was received by a different band
mixing scheme, then a pre-selector is peaked for resonance.
I wouldn't like to see the disappearance of WWV/WWVH but it would be for the
wrong reasons, mostly nostalgic. Some folks have commented on WWV's
minuscule operating expense when compared to the total federal budget, but
the problem with that thinking is we have thousands of federal programs and
departmental budgets that also contribute just a tiny fraction to federal
expense. Collectively, it adds up to a much larger figure. No matter what
goes away, the impact is felt by someone.
On the other hand, if WWVB remains due to the large number consumers who
depend on it for wall clocks and wristwatches -- and if a minimal staff and
infrastructure is required anyway, then perhaps an argument can be made for
the retention of WWV.
In the shack, I use a GPSDO with a distribution amp that locks several
transceivers and some test equipment. A surplus $100 USD rubidium standard
is Velcro-strapped to my HP frequency counter. It comes up to temperature
and locks within 5 minutes of powering. The accuracy of both devices far
exceeds my needs.
Paul, W9AC
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