On 24/12/2016 10:54, Dave Plowman (News) wrote:
In article ,
Andrew Gabriel wrote:
Your best bet to avoid this is to buy from reputable electronics
supply chain, but that's still no guarantee.

It sounds like the ones you bought were produced extremely cheaply;
poor quality LEDs and too little phosphor. At a couple of years old,
they can't have done even 20000 hours, even if used 24/7.

Because of the time of year and possibly slower postage, I've just
replaced them with the identical spares I had. Which will at least sort it
for some time.

But will get some better spares for next time. Any suggestions for the
most reliable supplier? The spec would be 5mm diffused warm white. They
don't need to be super efficient or whatever, as power isn't a problem.

AT the risk of degrading their longevity due to vibration and if you are
intending to use them for what I think then you can make a cylindrical
lens by very carefully drilling though the clear plastic of the water
clear type to make a spread beam in one dimension.

Expect to trash a few before you get it right. I don't know why makers
dont package some in a water clear cylindrical negative lens for diffuse
area illumination for side lighting older meter displays.

--
Regards,
Martin Brown