On Wed, 12 Jul 2006 21:34:59 -0400, the renowned "Fred Mann"
wrote:


"Chris Jones" wrote in message
...
Fred Mann wrote:

Hello,
I have a piece of audio gear which has an illuminated power switch. The
LED inside flickers. Should I replace the LED, or is something else at
play here? I was under the impression (for no good reason) that LEDs are
like light bulbs - either they work or they don't -- no flickering.
Thanks!!
Fred

Are you sure it isn't a neon tube? They do sometimes flicker when they
are
old.

Chris

I took the switch apart, and the "light" may in fact be a neon tube. It
looks like a very small condom with a reservoir tip (sorry, but that's just
what it looks like. I'm not sure if this is an LED, but the size is similar.
Thanks again,
Fred

Yes, it's a neon. The tip is where they sealed off the glass tube in a
hot flame.

You can replace the neon bulb itself, but take note of the series
resistor and size of the envelope (for example):

http://www.chefung.com/neon/neon.html

If you mismatch the resistor and the neon you'll either get too little
light or shorten the lifetime.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com