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Regulated 12v Supply, Hum reduction

Ok, so I have my old 12Vdc 6 amp power supply, with TONs of fresh electrolytic capacitors, but Im still getting a bit of 60cycle hum. I doubt that I will ever be pulling more than 2 amps from it, but it is rated at 6 amps.
Can someone suggest a choke, capacitor combo that will finish off the last bit of hum...something I can get from EBAY.
I remember back in the 70s when I had a power supply for my Radio Shack CB Radio with a bit of hum, I pulled a random choke out of a box of military surplus components from POLY PACKS (remember them). I had no idea of its rating, but I had zero hum from then on.
15 years later I sold it, and it was still perfect, and I never knew what the hell the choke was.
 
Most power supplies use a full wave rectifier bridge that produces 120Hz, not 60Hz. Then one or two of your rectifier diodes do not work.
 
Its only a slight hum, but noticeable. I did not realize that the bridge rectifier changed it to something other than 60 hz.
This does use a big, chunky full wave diode bridge module, mounted to the case for heat dissipation, I can only guess.
This is all followed by several high value electrolytics.
I changed the electrolytics to fresh ones, since I had them kicking around.
 
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