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Re: Flashlight runs even when off

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El 12/03/2026 a las 22:47, micky escribió:
> I have several little LED flashlights, 2 1/2" long and 7/8" in diameter,
> and on one the pushbutton switch on the end broke. OK.  But yesterday I
> notice that on another, my favorite one because the light was so bright,
> even after I turned if off, it was still casting some light.  I
> unscrewed the end with the switch and the resistance, when the switch is
> off if 168K ohms.  Turned it on and off and it was 145K ohms.  on the
> 200K ohm scale.  On the 2M ohm scale, it was 1.7M ohms.
> 
> Even the lowest of these values seems to limit the crrent too much to
> get light out of an LED.  What do you think about all this .

Modern hi-efficiency LEDs generate enough light to be visible with just 
a few microamperes. The eye can see light with just a handful of photons 
(think of viewing a star).

An open switch must have infinite resistance; humidity or external dirt 
may got inside, or metallic powder fallen from the contacts may create a 
path for the current. I have seen both cases.

-- 
Saludos
Miguel Gimenez

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Thread

Flashlight runs even when off  micky <NONONOmisc07@fmguy.com> - 2026-03-12 17:47 -0400
  Re: Flashlight runs even when off "Carlos E.R." <robin_listas@es.invalid> - 2026-03-13 14:07 +0100
  Re: Flashlight runs even when off Miguel Gimenez <me@privacy.net> - 2026-03-13 17:01 +0100
    Re: Flashlight runs even when off micky <NONONOmisc07@fmguy.com> - 2026-03-13 21:59 -0400
      Re: Flashlight runs even when off Miguel Gimenez <me@privacy.net> - 2026-03-15 13:15 +0100
      Re: Flashlight runs even when off Jeff Liebermann <jeffl@cruzio.com> - 2026-03-15 09:58 -0700
        Re: Flashlight runs even when off ehsjr <ehsjr@verizon.net> - 2026-03-15 17:38 -0400

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