Place the DC regulated power supply above the grounding plane by 25mm, with the grounding plane made of aluminum or copper. The common output terminal of the DC regulated power supply and the AC input ground terminal should be directly connected to the grounding plane. The grounding wire should be thick and not less than 50mm. Aeronautical Power Supply
A 300mm long twisted pair wire, made of 16AWG copper, is connected to a power output at one end, and a 47μF tantalum capacitor is paralleled at the other end, which is then connected to an oscilloscope. The capacitor leads should be as short as possible, and be careful not to reverse the polarity. The oscilloscope probe's "ground" should be connected to the ground loop as much as possible. The oscilloscope bandwidth should not be less than 50MHz, and the oscilloscope itself should be grounded for AC.
Output Noise Tests (including Peak-Peak Noise, Telephone Weighted Noise, Wideband Noise, and Discrete Noise). 400Hz Frequency Converter Power Supply
