Jim Lux wrote:

Why not take the GPS disciplined oscillator (e.g. a Z8301) and use that
to synthesize a fake WWV signal (which you could program up in the AVR),
and radiate that to your MACII. You can easily divide down the 10 MHz
from the oscillator to generate all the needed modulations for WWV (the
tones, ticks, and 100 Hz timecode). Synthesizing the voice
announcements might be a bit more challenging grin "At the tone,
Coordinated Universal Time is...." You could even have a switch to
change back and forth between WWV and WWVH.

Talking clock programs have been around for a long time. All you need
is samples for 0 through 24, 30, 40, and 50 and a few words. You could
even play games with it, I'm sure the clock does not care, for
example "At the beep, the fake univeristy time is" and so on.

You really don't need to do much at all, since if I remember correctly,
it's an AM modulated signal, with no modulation also being no carrier.
Am modulation and on/off switching of a high power radio signal is
fairly complex, but at the microwatt level it should be easy.

It's fairly slow so even a reed relay connected to a GPIO line
would do. I'm sure there are all sorts of digitaly controlled
analog switch chips that will quickly and cleanly switch 10mHz.

As an aside, if I remember correctly, the 60kHz version is just
pulse code modulation of a carrier at a very slow baud rate,
so it would be really easy.

Geoff.

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