[time-nuts] DCF77 question

[asmagal at fc.up.pt]

QUOTE:

"DCF77 marks seconds by reducing carrier power
for an interval beginning on the second".

UNQUOTE

This is not a good (Heaviside step) time marker.

Is it possible to decode that signal by any very
simple "on-my-shelf gear", as for instance a PC
sound card,to recover a good seconds time mark?

Do you know some software to perform the above task?

Thanks for reading.
Antonio
CT1TE