Do failing LEDs flicker?

Probably lead-free soldering cracking up!

Are you sure it's an LED? Neon lamps flicker when they get old.

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

Chris

LEDs can and do go intermittent. There is a particular model of Sony mini HiFi, which uses a LED bar to illuminate the see-thru LCD panel on the front of the tape deck door. It is very common for these to go intermittent and flicker. However, in this case, I am inclined to agree with the rest that it's more likely to be a neon lamp, that's just worn out. Usually easy to tell. If the switch just has two or four spade connectors for switching the line power, then the internal illumination will be by neon lamp.

Arfa

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 don't think this is an LED, but the size is similar. Thanks again, Fred

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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

If it flickers, it is a neon bulb.

Yup! NE-2 or similar.

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):

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

Best regards, Spehro Pefhany

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Thanks! Is my local electronics store likely to have a replacement? If so, will the resistor be matched up with the bulb when I buy it, or do I have to bring the original resistor in (I accidentally chopped it in half trying to bypass it -- don't ask). Thanks yet again!!!!! Fred

Hi...

Someone up there likes you! :)

Be very very thankful that your attempt to bypass it failed :)

Take care.

Ken

Go to your local electronics store, and ask for an NE-2. If the mains voltage is 120 VAC, ask for a 120 kohm 1/4 Watt resistor. If the mains is

As for the resistor, it is not very critical. For 120 VAC, you can use anything from about 100 kohm to about 140 kohm. Double this value for 220 VAC operation. If you go higher with the resistor value, the lamp will be a little dimmer. If you go lower, the lamp will be a little brighter. If you go too low, its lifespan will be reduced.

You may have to buy these parts in a minimum quantity, unless the dealer has opened packages of these parts in stock. Most distributors have a minimum invoicing. You may have to shop around for a small quantity.

--

JANA _____

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are

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similar.

Thanks! Is my local electronics store likely to have a replacement? If so, will the resistor be matched up with the bulb when I buy it, or do I have to bring the original resistor in (I accidentally chopped it in half trying to bypass it -- don't ask). Thanks yet again!!!!! Fred

that depends on how good they are.

it may be easier (but not cheaper) to replace the whole switch with another neon illuminated switch.

OTOH you should be able to get the data on your replacement neon so you can pick the apropriate resistor for it and the voltage it's supplied from.

has

Thanks all!!! I got it working. Fred

Also many 1/4W resistors are not rated for 240VAC use, but you might be able to put two in series to get sufficient voltage rating if you can't get the proper rating in a single resistor from your source of components.

Chris

I've seen it, but it's rare. Neon glow lamps often flicker as they get old though.

In a pinch, buy one of those little round neon nightlights and take it apart.

And the source for this little bit of misinformation would be?????

Jim

Which piece of (mis)information?

Here is an example of a 1/4W resistor not rated to 240VAC usage. I didn't have to look at many types of resistor to find it, it was the first datasheet I looked at.

There are plenty of resistors rated at 200 Volts. That is not enough for use at 240VAC (340V peak). You don't have to believe me if you don't want to, however the approvals bodies may disagree with you.

Chris