The Auxiliary Coil can be used to apply crossed magnetic fields vertically with respect to the tube axis, if the coil is mounted on the universal holder between the Helmholtz coils.
Such fields can be used to demonstrate the horizontal deflection of cathode rays in the Perrin tube (U18554) and, thus, the basic principles of a cathode-ray oscillograph, for example in generating Lissajous figures. Specifications Number of coil turns: 1000 Load rating: max. 2.0 A DC resistance: approx. 7.2 ? Connections: 4 mm safety jacks