Microwave Smoothing Choke

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This Hi-Fi power supply smoothing choke was made from a microwave oven transformer. The mains and heater windings were removed and the two magnetic shunts punched out. The remaining H.T. winding has a DC resistance of 140 Ohms. The correct gap turned out to be .01 inches. The old transformer was sliced open between the I and E laminations, the gap inserted, and then the two bits glued back together again with 'Araldite'. I glued on four sides and a top, and mounted a set of lugs with captive nuts onto two of the sides internally. All edges and corners were filed down, and a rub of fine emery cloth and 3 coats of black spray-paint will make it fit to grace the deck of any high end audio amplifier. By the way, the inductance measured out at a massive 102 Henrys, with a D.C. current of 160 Milliamps.