If you are interested in some great radio historic artifacts including a
recording of Major Armstrong doing FM tests on the old 112MHZ two and a
half meter amateur band in 1936, check out this site.
http://arizona-am.net/Armstrong/index.html
There are other recordings of FM experiments from the early days from
the 30's through the 50's.
Enjoy.
--
Dave Marthouse N2
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