On Tue, 18 Aug 2009 22:26:03 -0700, isw wrote:

But even the "best" receiver still wouldn't solve the multipath problems
that plague the MW bands.

How much accuracy are you looking for in a PC clock? I doubt that WWV
will give you millisecond PC clock accuracy, but it's more than
suitable for nailing it withing one second. Averaged over even a
fairly short period of time, the 2.5/5/10/15/20Mhz frequencies are
quite accurate. For re-synchronizing the clock, the time ticks are
also sufficiently accurate:

WWV Frequency Accuracy
As transmitted: 1 part in 100 billion
As received: 1 part in 10 million

WWV Time Tick Accuracy
As received: 1 millisecond plus propagation delay

WWVB Frequency Accuracy
As transmitted: 1 part in 100 billion
As received: 1 part in 100 billion

The major ionospheric multipath problem is the almost 180 degree phase
reversals from constant path switching as the various incident and
reflected signals fade in and out. Yeah, that's going to be a
problem, but due to the limited accuracy required in a PC, it's not a
big problem.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558