Quite coincidentally, I wrote an article for the current Player Piano
Group bulletin on this subject (it's in the post to subscribers as I
write).  There's a web site, written by Antheil's son, which contains
the patent and a few articles about it.  See

  http://www.ncafe.com/chris/pat2/index.html

For those not aware what this is about, the patent was to use synchro-
nised piano rolls at transmitter and receiver to shift the frequency a
radio signal was broadcast on, the arbitrary shifts from one frequency
to another preventing jamming or eavesdropping.  The basic application
was to control a torpedo (even though a piano roll in a torpedo does
seem rather far-fetched), so the breaks as the system shifted from one
frequency to another were not important.

I read through the patent and was impressed both by the wonderfully
clear manner in which it put its case, and by the sheer elegance of the
ideas which it incorporated, both the practical detail and the general
concept behind it.  It's well worth reading.

In case it seems just too implausible that someone of Hedy Lamarr's
background should be able to carry off such a venture, one of the
articles describes how Lamarr and Antheil benefited from the National
Inventors' Council, which had a scheme to assist amateurs work up the
ideas.  Someone at Massachusetts Institute of Technology was contacted
to provide technical assistance.  It seems reasonable to ascribe the
torpedo control idea to Lamarr, the piano roll coding idea to Antheil,
and the form of the system to the MIT and other advisors.

Julian Dyer

 [ Frequency hopping radio systems were fielded much later, in the
 [ 1950s I believe, after both radio and crypto technology advanced
 [ enough to make the invention practical.  The meager funds available
 [ during WW2 for development were used for more immediate needs like
 [ radar for gunfire control and self-protection.
 [
 [ MMDer John Dewey wrote to me that an article about the patent
 [ appears in Invention & Technology magazine of Spring 1997;
 [ reprints are available from Invention & Technology, Scientific
 [ American, P.O. Box 2062, Harlan, Iowa, 51593; tel. (800)-624-6283
 [ -- Robbie