[Lowfer] WWVB clock on 60 kHz

[Garry]

Hi Mike,

Glad the wspr-15 came through for you from lowfer SIW.

Interesting idea to try a LPF to block broadcast signals. I've had a 
high-order band-reject filter collecting dust because I figured the 
eprobe itself was generating the interference, not my sdr-iq receiver. 
But it was easy to check what happens when the filter is placed in-line 
between the eprobe and sdr-iq. As for decoding the clock information 
from WWVB on 60 kHz, no go. But France-inter on 162 kHz still works fine 
and DCF77 on 77.5 kHz looks much better, though too weak to decode (JJY 
on 40 kHz was also too weak; it should improve as local sunrise nears). 
I liked the cleaner look on the waterfall and at 15-30 kHz the 60-Hz 
harmonic comb level is reduced, allowing, for example, JXN on 16.4 kHz 
to be evident on the waterfall. Bottom line - I think I'll keep the 
filter in-line except when tuned for Navtex on 518 kHz, which is 
slightly above the filter cut-in frequency. Thanks for the suggestion.
-- 
Garry, K3SIW, EN52ta, Elgin, IL