[LEAPSECS] DCF 77

[David Malone]

> Remember that I am somewhere around 1000km from the transmitter, there

> isn't that much signal left when it comes here.



> I'm not sure what the electromagnetic mechanism for the extincion is

> but it is quite notable.


I saw something interesting with the MSF signal in Dublin during
some recent thunder. I managed to catch the lightening with a
software radio, and drew the spectrogram:

	http://www.maths.tcd.ie/~dwmalone/lightening1.png

The big bright vertical line is the lightening. If you look around
60kHz, you can see the Rugby signal invisible before the lightening,
but completly clear afterwards. I'm about 260km from the transmitter
and the lightening was almost overhead. If you squint, I think you
can see a similar but weaker effect for DCF.

	David.