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Reporting question for Kit - Pine Board Power Supply with 3 Outputs

Product:
Kit - Pine Board Power Supply with 3 Outputs

Question:
How do I filter AC hum out of it? On two radios I tried there was a low but audible AC hum. I'm thinking this is coming through the A supply to the 01a filaments

Answer:
.01uF caps across the bridge rectifiers as follows- on the + side of each bridge solder one lead of a pair of .01 caps. The other end of one cap goes to one of the AC input leads, the other lead of the second cap to the second AC lead. Do the same for the - side of the bridge to the AC leads. (total of 12 caps.) Make sure the ones across the high voltage winding are at least 600V rated.