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David Merrill discovers unintended sound effects from an LED display:
"I didn't realize that an LED could make *audible* sound until my friend/colleague Sajid called me over to have a look. What can I say - it's true.. This is a circuit with NO SPEAKERS, making audible sound.
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Comments (3)
.. as opposed to *inaudible* sound?
Posted by Andrew | March 12, 2008 2:14 PM
I wonder if the noise is coming from ceramic capacitors (piezo electric effect) or from any coils in the circuit?
Posted by Steve Winder | March 12, 2008 5:09 PM
That would have been my guess, I have often seen this with very cheap switchmode psu designs, when the current is modulated.
Posted by Doug Allender | March 13, 2008 9:51 AM