Abstract: A multilayer printed circuit board includes an inner magnetic layer essentially consisting of magnetic material. The inner magnetic layer may be formed by an action of chemical bond or van der Waals force. The inner magnetic layer may comprise a plurality of magnetic units, each of which provides magnetism, and may be formed by magnetically coupling the magnetic units with each other by using a strong interaction. The inner magnetic layer may essentially consist of a ferrite film. The ferrite film may be formed directly on the inner conductive layer by means of an electroless plating method. The ferrite film may essentially consist of an oxide metal composition, the metal composition being represented by the formula of FeaNibZncCod, where: a+b+c+d=3.0; 2.1?a?2.7; 0.1?b?0.3; 0.1?c?0.7; and 0?d?0.15.

Abstract: A multilayer printed circuit board includes an inner magnetic layer essentially consisting of magnetic material. The inner magnetic layer may be formed by an action of chemical bond or van der Waals force. The inner magnetic layer may comprise a plurality of magnetic units, each of which provides magnetism, and may be formed by magnetically coupling the magnetic units with each other by using a strong interaction. The inner magnetic layer may essentially consist of a ferrite film. The ferrite film may be formed directly on the inner conductive layer by means of an electroless plating method. The ferrite film may essentially consist of an oxide metal composition, the metal composition being represented by the formula of FeaNibZncCod, where: a+b+c+d=3.0; 2.1?a?2.7; 0.1?b?0.3; 0.1?c?0.7; and 0?d?0.15.

Abstract: Noise detection devices are placed at arbitrary measurement points. A selection device switches the output of the noise detection devices and an analyzer analyzes the noise amount of the frequency component for each frequency band of radiated noise. A comparison device is made up of a storage section for storing measurement data provided by a plurality of the detection devices and a comparator, and finds a difference and a greater-than, equal-to, or less-than relationship between the noise amount analyzed by the analyzer and a predetermined value in a full band or at a specific frequency or a difference and a greater-than, equal-to, or less-than relationship between the noise amounts at two points. Output of the comparison device is displayed on a display device.