Eberhard & Co was one of the early adopters of a Faraday cage to protect the delicate balance of their mechanical movements from the effects of magnetic fields when it created its Scientigraf watch in 1961.
The Faraday cage is a simple concept. Magnetic fields affect watch precision because parts in a movement are made from different metals that respond differently to the force.
For example, a magnet will have almost no attraction to copper gold but a strong attraction to steel.
Iron is at the end of the scale with the greatest attraction, which is why it is used to absorb magnetism in a Faraday cage.
Precision is less prized in traditional mechanical watchmaking today than it was back in the pre-quartz days of the early 1960s, but magnetic fields are a much bigger problem because of all the electronics we now use.
That is why Eberhard continues to reissue the Scientigraf, and has a new steel on steel pilot-style model for 2021 in a 41mm 100 meter water resistant steel case.
There is also the option of a fabric strap.
The latest models will be unveiled later this month to American buyers at Couture in Las Vegas.