Capacitive tuning screw

摘要

A capacitive tuning screw comprises a threaded portion with a longitudinal cavity for slidably receiving a plunger shaft. If the capacitive element on the tip of the plunger shaft contacts the corresponding capacitive element on the surface of an electrical circuit board or substrate, further turning of the screw will cause the shaft to slide into the cavity and prevent crushing the circuit board or substrate. A shoulder on the screw stops rotation and longitudinal movement of the screw before the entire length of the plunger shaft slides into the cavity.