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Old 01-26-2012, 01:52 PM
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wa2ise wa2ise is offline
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Join Date: Dec 2002
Location: USA
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Quote:
Originally Posted by maxhifi View Post
This one is all on one PC board, and the knobs can't come off. I'm not that worried about safety.

I noticed something interesting last night; the hum continues when the radio is off. The clock motor is mechanically transmitting vibrations through the cabinet to the speaker cone, which is adding to the 60Hz noise.
To improve safety here, you can rewire the clock radio power switch to switch the line that goes to the rectifier tube, and hard wire the line that goes to the radio's ground. And the line that goes to the radio's ground should go to the power plug's neutral side (on a modern 2 prong power cord, the wider of the two prongs).
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