4.4.2　Experimental instruments

GD-3 Planck constant measurement experimental system is shown in Figure 4.4.1.

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Figure 4.4.1　GD-3 Planck constant measurement equipment

1—mercury lamp;2—color filters;3—photoelectric tube;4—current rate switches;5—microammeter;
6—DC voltmeter;7—current zero adjustment knob;8—Voltage regulation