electronic signal generators; electronic signal analyzers used to measure the parameters of the signature in electronic circuits; electronic frequency counters used to count the frequency of the signature in electronic circuits; digital multimeter used to measure the AC (alternate current)/DC (direct current) voltage, current, resistance, capacitance and continuity in analog and digital circuits; digital panel meters used as digital output displays for test instruments; temperature testers used to measure the temperature of electronic components or equipment; automatic test equipment; namely, linear/digital integrated circuit testers, printed circuit board testers, logic monitors and logic comparators; electrical cable testers; LCR (inductance, capacitance, resistance) meters; clamp-on current meters and watt meters used to measure the driving current and power dissipation of electrical equipment; electrical power supplies; EPROM (erasable programmable read only memory), EEPROM (electrical erasable programmable read only memory), PLD (programmable logic device), EPLD (erasable programmable logic device) programmers; fiber optic test equipment used to measure the transmission parameters and light power of the fiber optic communications