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Humming coming from power adapter
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Humming coming from power adapter

by hcmustard on Sun Sep 23, 2012 4:55 pm

Hey everyone.
I just received new power adapter for the Raspberry Pi -

As far as I can tell it has been working great. Test voltage on it, ~5.18v stand alone, lowest I've seen it was ~4.90v under load, with network, hdmi and 2x usb still working fine.

However the adapter itself is emitting a humming noise.

I tried other power adapters and they did not make any noise (that I could hear), however they weren't high enough v/amp for what I need.
I've tried different wall sockets, and I've tried it with just the adapter plugged in, not even USB cable to it, so I know it is the adapter itself.

Is this indicative of something that is or may become problematic, or is it nothing to worry about?

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Joined: Sun Sep 23, 2012 4:39 pm

Re: Humming coming from power adapter

by adafruit on Thu Sep 27, 2012 10:02 am

The humming is part of the switching supply, its not a problem, and normal for the supply!

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