This added voltage is mainly power line frequency and its effect on the voltmeter reading will depend upon the normal-mode rejection capability of the meter.

这个相加的电压主要为电源频率的信号，其对于电压表读数的影响决定于电压表的串模抑制能力。

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Cost and Capability: Cost concerns alone should dictate rejection of a completely ground-based defensive system in favor of one that uses both ground and space elements.

CENTERFORSECURITYPOLICY: Center For Security Policy