Abstract: A fixture for holding a semiconductor die against an abrasive media for the purpose of thinning the die is described. The fixture provides means for aligning the back of the die to a reference plane that is coplanar with the plane of the abrasive and is in contact with the abrasive media during the thinning process.

Abstract: A wireless system is provided for switching the pickups of a guitar. The system may work in conjunction with MIDI devices such as effects processors. The system includes a transmitter and a receiver. The transmitter receives input from the MIDI device via a DIN connector and generates a control signal which corresponds to a preselected combination of pickups which have been programmed and stored in memory. A second DIN connector is provided to function as a pass-thru. The pickup combinations stored in memory are associated with a program from the MIDI device. A display is provided to indicate to the musician which program is in current use. The receiver is positioned within the cavity of the guitar and includes a plurality of relays coupled to the pickups of the guitar. Based on the control signal received, the relays are activated in order to provide the selected pickup combination.