If WWVB is 2800km from us, then the signal takes 9ms to get here. Assuming
the shape of the pulses is the same as for MSF ie a carrier break for 100 -
300ms timed to start exactly at the UTC second , then there will be a period
from UTC +0 to UTC + 9ms when it ought to be possible to receive WWVB during
the MSF off period. By gating out the received signal and coherently
averaging, we can now have .009 / 1s worth of WWVB data, ie a signal strength
20dB below what would otherwise be possible. With GPS based timing, deriving
this gating period is trivial, but even witout GPS, MSF can probably be used
itself to generate the timing
I'm not proposing to do this, just throwing an idea into the ring ;-) but know
how you like to take on challenges Jim.
Andy G4JNT
In the UK we have MSF, also on 60kHz, which is a big signal here (several
millivolts/metre) - so I am unlikely to ever hear WWVB at my QTH! RX
antennas are a variety of tuned wires and loops, usually whatever is giving
the lowest level of mains-bourne noise at that particular frequency and time.
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