"Richard Clark" wrote
...
On Mon, 11 May 2009 11:35:41 +0200, Szczepan Bia?ek
wrote:

doubling is possible.")?

No.

Here is wrote that it happend:
http://books.google.pl/books?id=QSke...P RA1-PA53,M1

There on the page 53 you can find that the medium-wave were disturbed by the
long-vave (halve-way between).
S*