old fastion ringer on phone?

Question

is there a site on the web were you can get the plans to build a ringer like they had in the rotor phones to show how magnets and electricity work?

Answer 1

It was just a relay coil pulling on a lever that hit a bell. The mechanical level part was tuned to work at the 20Hz ringing frequency, so that it hit the bell loudly.

You may still be able to find an old phone with a electro mechanical ringer at a garage sale.