物理
电动打孔器
凹凸桥演示器
液体表面张力演示器
磁学套装
感应器电机
AV-2800T
AV-2800T
Epidiascope
Electronic metronome
Experiment of transducer arithmomter
Frequency spark counter
Electromagnetic bribe timer
Teaching oscillograph
DC voltmeter
Demonstrator of ammeter principle
Simple resistor
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