A fixture and technique for testing a coil spring selected from a supply of springs. The upper surface of the strained semiconductor layer may be roughened andor contain a dielectric layer or silicide which may be patterned to trap the upper end of dislocations in selected surface areas. An aiming cursor linking control unit 224 moves and displays the aiming cursor K in the display unit 211 such that the aiming cursor K is linked with a movement of the manipulation icon CM that is moved and displayed by the manipulation icon display unit 222. A gasket may be engaged between the port of the block and the fitting, and may include one end engaged into the port of the block. The acoustic sensors are connected to data processing equipment for analyzing sounds picked up by the sensors for acoustic signals indicative of insect infestation.