Check out http://www.k1ttt.net/subharmonics/subharmonic.htm for the
circuit I used and picture of scope traces. It is bigger than I wanted
so it may take a while to download.
As for the use of 'subharmonic', by the definition in the IEEE Std
100-1996 "The IEEE Standard Dictionary of Electrical and Electronics
Terms" Sixth Edition the word 'Subharmonic' is defined as "A sinusoidal
quantity having a frequency which is an integral submultiple of the
fundamental frequency of a periodic quantity to which it is related. For
example, a wave the frequency of which is half the fundamental frequency
of another wave is called the second subharmonic of that wave."
It is not defined by how it is produced, simply by the mathematical
relation between the two frequencies. That it is caused by injection
locking of an oscillator as in that IEEE paper that has been referenced,
or in this case by injection locking a ringing transmission line segment
is not important. It may be a misunderstood term and rarely seen, but
it is a valid electronic term.
David Robbins K1TTT
e-mail: mailto:k1ttt@arrl.net
web: http://www.k1ttt.net
AR-Cluster node: 145.69MHz or telnet://dxc.k1ttt.net
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