In article ,
Martin Brown wrote:
Only LEDs I've had which deteriorated - rather than fail - were some
cheap warm white low current types. They got dimmer and dimmer -
despite being conservatively driven.

That is quite unusual. The only power LEDs I have ever seen dim with age
have been on inadequate heatsinking and run *very* hard. After a while
you can see blackening of the previously yellow phosphor and yellowing
of the nominally water clear plastic lens.

These looked perfectly normal. They were used to illuminate a meter -
replacing the original pea bulbs.

I just assume I got a bad batch somehow. They were pretty cheap ones from
China via Ebay. Not silly cheap though. Replaced them using exactly the
same drive electronics, and those have been fine.

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*IF ONE SYNCHRONIZED SWIMMER DROWNS, DO THE REST DROWN TOO?

Dave Plowman London SW
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