crystal vacuum tube voltmeter
logarithmic vacuum-tube voltmeter
plate-detection type vacuum tube voltmeter
slide-back vacuum tube voltmeter
ultra-short wave vacuum tube voltmeter
vacuum tube voltammeter
very high frequency vacuum tube voltmeter
VHF vacuum-tube voltmeter
digital voltmeter
数字电压表
直流数字电压表
数位式电压计
数字式电压表
数字伏特计
数值电压计
direct current digital voltmeter
integrated digital voltmeter
integrating digital voltmeter
portable digital voltameter
smart digital voltmeter