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Eh? What.

There is actually a picture of the dial tone generator in Flickr. Motor was moving generators on various speeds. https://www.flickr.com/photos/9479603@N02/1814546737/in/phot...

As regards to logistics of tones and stuff. You dont want to know. It involved multi-level signalling of currents and voltages.

I am the ultimate expert. I wrote a thesis on Coin-operated Telephone signalling in 1977.




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