Industrial electronic repair services often provide expertise in repairing specific types of equipment and instrumentation. Some companies repair acoustic sensors and microphones, automated test equipment (ATE), data and chart recorders, data acquisition and signal conditioning equipment, displays and panel meters, or electrical testers. Other companies specialize in repairing generators, industrial computers, machine controllers, motor drives, electrical meters, scopes, power supplies, and amplifiers. Industrial electronic repair services also fix printed circuit boards (PCBs), control systems, servo drives, sound level meters, timers and counters, signal and function analyzers, and welding machines. In terms of instrumentation, industrial electronic repair services fix products for avionics, calibration, fiber optic, laboratory, marine, medical, geophysical, and vehicular applications.