Second day of Chaos Communication Congress here in Berlin. Sorry, no images from the first day.
You can see history here. The new telephone at the left and the old one at the right. Left of the old one is a relay station which counted the rotations of the dialer. This really worked here (i filmed it, watch out my blog site the next days, I'll upload some of them in the new year), it was loud and you could see the whole thing working!