(a) A transformer in a power supply operating at 15 kHz must be isolated from the rest of the circuitry to avoid couplin
Posted: Tue Jun 07, 2022 11:37 am
(a) A transformer in a power supply operating at 15 kHz must be isolated from the rest of the circuitry to avoid coupling and unwanted noise. Determine if a 0.8 mm T2 Copper plate (99.9% purity) at US$57 per sheet (300 x 300 mm) or 0.9 mm mild steel sheet at $16 (300 x 300 mm) enclosure would provide better shielding. Assume that there are no openings or apertures. Do this by calculating the following: (i) The transition distance between near and far field zones. [1] The skin depth of the materials. [2] (ii) (iii) The impedance of both materials at the operating frequency. [2] The absorption of both shields in dB. [2] (iv) (v) The reflection loss of both shields in dB. [2] (vi) The total shielding effectiveness of both materials. [1]