Triboelectric amplifiers

I recently asked on sci.physics.research about the principle of triboelectric amplifiers, a topic ignored in modern texts. I wrote:
"The tribo-electric amplifier is exemplified by Edison's Electromotograph telegraphic relay and Chalk telephone, and as I remember, a WW2 German loudspeaking megaphone, which may have used a dry mineral rotor (Agate?).
In the Chalk telephone, a small dampened chalk cylinder is rotated quite slowly. A spring leaf connected to a diaphagm is pressed quite hard on the chalk. A voltage between the spring leaf and the chalk varies the friction acting on the spring leaf, causing the diaphagm to move in and out in accordance with the applied voltage. Evidently quite low voltages and currents are effective.
A certain amount of basic information can be Googled, but I'd like to find out more about the effect and it's principle, and I'd appreciate it if anyone can offer any references."
Although no-one responded on the research N.G., I was eventually able to find information at:
http://www.research.ibm.com/journal/rd/011/ibmrd0101H.pdf
I share this with the group in case anyone out there is interested in physics etc.
All the best
Ian Macmillan

Ian Macmillan wrote: <snip>
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Thanks! I am reading the article now....

On Wed, 17 May 2006 21:23:54 +1000, "Ian Macmillan"
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Rings a bell faintly. I dimly recall a patent by Snelling assigned to Xerox which modulated a signal based on triboelectric behavior.
A search of USPTO files revealed no clues. The reverse is possible-- that I sent Snelling the description based on his interests. Using the capstan effect with electrostatics modulating the action rings the bell even louder but as yet, no cigar. If you are really interested, I can phone Snelling and ask. He might remember from perhaps 20 years ago--I don't.

Is anyone an expert of nanocomposite or silicon carbide ceramic?? Is anyone doing some work on the either subject??
??????: snipped-for-privacy@4ax.com...
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