Lossless continuously adjustable devices

An apparatus comprising:

• an adjustable device, wherein the adjustable device comprises one of an adjustable translational mechanical device, an adjustable rotational mechanical device or an adjustable electrical device, and wherein the adjustable device comprises an adjustable rotational mechanical device, the adjustable device including:
• a plurality of terminals,
• an assembly that is freely and independently moveable between internal components of the adjustable device, wherein a movement between the internal components causes a parameter of the adjustable device to be changed, and
• a linear actuator coupled to the assembly that is configured to impose the movement that causes the parameter of the adjustable device to be changed,
• wherein the internal components include a pair of rotating cones having respective surfaces separated by a gap having a fixed distance between the respective surfaces, and the assembly is moveable in the gap, and
• wherein a first one of the cones is fixed with only a freedom of rotation, and wherein a second one of the cones has both a freedom of rotation and another freedom of movement with respect to the first one of the cones.