Turns out that what I thought would be a quick test, became anything but. After writing a preliminary WWVB decoder and display driver, I hitched the receiver up to a Z8 dev-board. Suddenly, there is no signal. Eventually, I worked out that the scope gave the receiver a very nice earth ground, and that using a 5V wall-wart for power took that ground away.
Because I am prototyping this on a solderless breadboard, I understood that the circuit's behavior would be a bit off from the calculated value. With the signal at 60kHz and using relatively low resistance values in the filter, a few picofarads shouldn't make a huge difference, right? There was some, so a few changes were made and some more gain was found.
There still remains to choose an antenna. A long-wire antenna is usually the easiest to implement, until one realizes that the wavelength of a 60kHz signal is 5km. Yeah, that's over 3 miles of wire! The Mountain House is on a fair-sized patch of nowhere, but even a quarter-wave would go way out of bounds. A ferrite rod from an A.M. radio could be pressed in to service, but would need re-winding. That could be a lot of effort for an insufficient result. A promising alternative is a loop antenna, specifically a "small" loop. The definition of small in this context appears to be an antenna that is less than 10% of the wavelength. I'm starting with 100 m. of wire...
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