Controlling magnetism in a device is not easy; unusually large magnetic fields or lots of electricity are needed, which are ...

The business ends of the reeds are coated with a non-magnetic material ... easily replaceable relay unit for switching telecommunications traffic, some kind of simple switch that could withstand ...

Latest among them is the video below the break from [Wim de Kinderen], who is demonstrating the workings of a mechanical crossbar switch ... for the magnetic flux to actuate the relay.

to separate magnetic materials such as iron and steel from non-magnetic materials; in electric bells; in relay switches and door locks that can be controlled remotely; to hold open fire doors ...