High pitched "squeel" or hum from UV flashlight

magician13134

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Jan 23, 2009
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My WF-502b light is pretty cool, but there's a high pitch hum coming from it. Sometimes it goes away for a bit if I shake it, but otherwise, it's pretty annoying. Is this normal?
EDIT:
Only with 2x123s, not 1x18650
 
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magician13134

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I wasn't sure. Some forums are different, a mod can join my threads if you want. They were unrelated topics, so I figured I would make a new one, sorry! :oops:
 

balou

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This has probably nothing to do with UV, but with the switching power supply, more precisely the Inductor used. You can try to damp it, with some hotglue or Blu-Tack.
 

Fallingwater

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It's normal. All of my multimode lights occasionally whine. My NDI always squeals at medium power, and the funny thing is it changes pitch if I whack it a bit :p
 

magician13134

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This has probably nothing to do with UV, but with the switching power supply, more precisely the Inductor used. You can try to damp it, with some hotglue or Blu-Tack.
Ok... Sorry to keep asking questions, but where would I find that? I assume it's in the module...?
 

balou

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see here for pics of a lot of different inductors. Generally, it's an iron core with shiny copper wound around it. On small size items it also often looks like a rectangular thingy with a visible circle in the middle. Fourth row, leftmost on the pic below.

http://www.lakewoodconferences.com/direct/dbimage/50159274/Transformer_and_Inductor.jpg

If it has a hollow core, fill that up with hot glue, and make a trail of glue from the hollow center to the board. If it's the second variety then just completely encase it in glue. Or BlueTack or similar if you want it to be removable.

My Nitecore D10 doesn't hum, but I silenced my Wifi router this way
 
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